Why Issue

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February 2008/Issue 19

think. what you can be

WHY...

IN? ? YUCKY SK

Smoking is strictly

for dummies

YEBO, 2008

? Are you ready for it – A N D H IP bassadors Meet your Brand Am

ART YOUNG, SM

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SLICE AWAY

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2 controller

Let’s take apart a PS

S W

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DO SHOWER CURTAINS ATTACK WET BODIES? PLUS 13 OTHER INTERESTING QUESTIONS*

DOGBREATH

HOME TRY THIS AT

of light Measure the speed ch d ocolate with a microwave an

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INTELLIGENT ENTERTAINMENT

Let’s get deep into 3-D movies • Jacques shakes off his Idols image • Brain busters that could make you cry dacovers.indd 1

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HERE’S YOUR CHALLENGE

Will you be able to navigate your way through the mag – and 2008 easily? Get your creative juices flowing by working your way through this maze. (You may go under the bridge.) Good luck on your journey!

CONTENTS FEATURES

• Quiz: are you ready for 2008?_p10 • Why, oh why? Your questions answered_p13 • Introducing the HIP2B2 Brand Ambassadors_p29 • Get into gear with cricket_p38 REGULARS

• Ed’s note_p2 • Community of Hip: your news, your views_p4 • Smart Technology: a virtual sign-language interpreter, earthworms that make compost and acrobots_p6 • Deconstruction: what’s inside a PS2 controller?_p8 • Body Smart: why smoking is a dumb idea_p22 • Sci DIY: measure the speed of light – with chocolate_p26 • Smart Maths: balancing equations_p36 • Think Tank: brain busters to start off the year_p47 • Simply Science: how does a remote work?_p48 INTELLIGENT ENTERTAINMENT

PHOTOGRAPH: COVER: GALLO/GETTYIMAGES.COM

• Press Play: what not to miss_p41 • Music: Jacques tells us about life after Idols_p42 • Movies: decoding 3D in film_p44 • Books: your views on Writing from South Africa _p46 CENTREFOLD

Start here

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• How to ask why in our 11 official languages

1/8/08 1:48:08 PM


work.’ st important part of the ‘The beginning is the mo - PLATO

and new of possibilities rld wo a it th wi UNKNOWN gs in e year sets the Each new year br u lay early in th yo n tio da un fo introductory adventures. The attention to the y Pa e. m co to rtain not to tone for things you’re almost ce d an s as cl hs at e now and you lessons in m anaging your tim m t ar ow, st ; ril Ap in June. Yes, I kn feel lost by ercome by stress ov be t no ll wi probably all before … urself you’ve heard it is year? Rate yo e you to face th ar y ad ich re wh w in ho e t Bu 10 and se ecklist on page ch r ou . er to rd g ha in t rd bi acco to work a e you may need ar with areas of your lif y started the ye ad re al who’ve You may s. or ad Some Hip stars ss 2 Brand Amba B P2 HI 13 ur yo d about them at a bang are TV show or hear e th on em th ans for 2008. have seen all about their pl ad re w No y your . ol ho your sc er wondered wh te: have you ev no nt re t around ie ffe di qu a is On when all es you by singing ss ly a star, rra al ba re t em y no s m tum g star when it’ tin oo sh a it ll swer all these you, why we ca in a circle? We an s ee gr de 0 36 e ue. or why there ar onth’s ‘Why?’ iss more – in this m ‘Why?’ for ng ki as u questions – and yo t by withou es go y da a estion: t no ry I’m sure ng that ve qu off the year aski t ar st swers. We an . r on fo as some re ch eagerly curious and sear ay st to u yo nt we wa ! usly smart 2008 Here’s to a curio NEVELIA

DON’T MISS IT!

Get ready for the scientific ride of your life. The International Time Council has sent an advanced neuroprogram entity (or ANE) back in time to take us on a whirlwind journey through 150 years of groundbreaking science. The HIP2B2 ROADSHOW will be visiting schools across the country from January 2008. Want to know if your school is on the hit list? Find out at <www.hip2b2.com>.

Editor Nevelia Heilbron Art Director Anton Pietersen Managing Editor Desireé Kriel Copy Editor Sally Rutherford Proofreader Fred Pheiffer Editorial Intern Nicklaus Kruger Publisher Helena Gavera Editorial Consultant Stefania Johnson Creative Director Crispian Brown Executive Editor Ami Kapilevich Production Manager Shirley Quinlan Reproduction New Media Repro Advertising Director Aileen O’ Brien • Tel: 021 417 1228 Advertising Executive Leigh O’Kennedy • Tel: 021 417 1116 New Business Enquiries Martha Dimitriou • Tel: 021 417 1276 Editorial Contributors Nikki Benatar, Ellen Cameron, Prof Alison Lewis, Jacqui Lund, Michelle Minnaar, Linda Pretorius, Anthony Samboer, Mark van Dijk, Michelle Viljoen, Mandy J Watson Syndication Manager Glynis Fobb Educational Consultants Wordwise PUBLISHED ON BEHALF OF BSQUARE COMMUNICATIONS Communications Manager Kate Evans HIP2B2 PIONEERED BY MARK SHUTTLEWORTH <www.hip2b2.com> Published by New Media Publishing (Pty) Ltd Tel: 021 417 1111 • Fax: 021 417 1112 <www.newmediapub.co.za> Managing Director Bridget McCarney Business Development Director John Psillos Editorial Director Irna van Zyl All rights reserved. While precautions have been taken to ensure the accuracy of information, the editor, publisher and New Media Publishing cannot be held liable for any inaccuracies, injury or damages that may arise. Printed by Paarl Print ABC 124 687

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PHOTOGRAPHS: JOHAN WILKE, • HAIR AND MAKE-UP: MARELI SERFONTEIN

CHAT ROOM

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RESPECT

AN RL

A

OC

IN

Favourite subject: maths; I’m good at it and it’s useful. Best part of the contest: the hip-hop dancing in the karaoke. Dream job: to develop medication for HIV/AIDS. Favourite scientist: John Dalton is smart, and he developed a really cool atomic model. SHABANI MALONDA, Malibu High

Favourite subjects: maths and physics. Best part of the contest: the karaoke – good music, good dancing and just altogether a good time. Dream job: chemical engineering. SH

A NI

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Favourite scientist: he’s not a scientist, but I admire Mark Shuttleworth for going into space. ARLAN THIELMAN, Malibu High

INNOCENT MFONO, Malibu High

A

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At the Grade 10 Sunzone Science Competition, Stellenbosch

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Since 2003, Roger Federer’s been helping children in the impoverished New Brighton township near Port Elizabeth. And in December last year, the ATP’s world-number-one tennis player and UNICEF Goodwill Ambassador starred in a campaign to raise awareness about the transmission of HIV from mothers to their children. Ace!

YOU SAID IT

Favourite subject: physics – I like the way it stretches my mind. Best part of the contest: The Weakest Link; I knew all the answers … okay, maybe not all of them. Favourite scientist: Isaac Newton. YOLANDA SAPTOU, Skoonspruit

High School

Favourite subject: life sciences. Best part of the contest: The Weakest Link – I felt like I knew all the answers. Dream career: I want to be a gynaecologist.

A

A while ago you featured a review of Linkin Park that I totally disagree with. Comparing them to Green Day is just sad – they don’t even belong to the same genre. They do not write only about teenage angst – and even if they did, it gives their fans, who probably are teens, something to relate to. I personally think their best project is Hybrid Theory and this is the CD they are best known for. But thanks for a great magazine and for actually doing reviews for the alternative scene; maybe you can include some metal next time? – RACH

YOLAN D

STINKIN’ PARK REVIEW

ENT

VOTE OF THANKS

I’m very impressed with the way HIP2B2 works to show young people that science is very important. I wish you could do even more. – TEBOHO MOHAPI

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Share your news, views and pictures – and please include your contact details, school and grade. • Write to: HIP2B2, PO Box 440, Green Point 8051 • Email: <talk2us@hip2b2.com> or <win@hip2b2.com>

YOU WROTE ...

Who do you nominate for the HIP2B2 badge of respect, and why?

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FORUM

Favourite subject: life science. Best part of the contest: the karaoke – it was nice to cheer and have a show and still have it be educational. Dream job: computers or programming. Favourite scientist: Albert Einstein – very clever guy.

A pica is a printer’s unit of type size, equal 1 to 12 points or about 6 of an inch (about 0,4 cm). It derives from the medieval Latin term for a list of church services. It’s also the name given to a type of magpie, and a strange craving for abnormal foodstuff.

SA V E TH E DA TE

T

Now you can text us your thoughts or ideas. SMS HIPCOM followed by your comments to 34978. Each SMS costs R2.

EN

African bull elephant.

4-D is the special term for a 3-D film that also has physical effects the audience can experience in real life, such as rain from water jets or mist sprayers, wind and confetti.

N U M B E R S

BRENT TAUTE, Klein Nederberg High

DID YOU KNOW?

5 tons is the weight of the

B Y

Favourite subjects: I like maths, physics and biology equally. Dream job: to be a chartered accountant – they make the big bucks. Favourite scientist: Chadwick – he discovered the Newton, and that makes physics interesting and useful.

BR

INTERVIEWS BY NICKLAUS KRUGER • PHOTOGRAPHS: DENVER HENDRICKS, MERWELENE VAN DER MERWE, GALLO/GETTYIMAGES.COM

VUYOKAZI STOKWE, Malibu High

Recently, HIP2B2 was honoured to win two PICA Awards at an event that celebrates excellence in magazine publishing. We brought home one of the most coveted titles: Customer Magazine of the Year. Rock on! The judges said this: ‘HIP2B2 is an exhilarating, fresh and effective magazine … In meeting HIP2B2’s objective of making maths and science appealing … the publishers deserve an A+, which in magazine terms is a PICA!’

Each of us knows of someone who’s battled with cancer. On 4 February, World Cancer Day, spare a thought for them and survivors like 16-year-old Nthabiseng Mabaso, diagnosed with leukaemia in 2005. • Leukaemia: cancer of the white blood cells, which are formed in bone marrow. It is classified by how quickly these cells multiply, either as acute (rapidly progressing) or chronic (slow progressing). Visit <www.momentsintime.co.za> for more.

H I P

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YOUR AWARD-WINNING MAG

25–26

March 1889 was the date of the first cricket test match held at Newlands, Cape Town. England beat South Africa by an innings and 202 runs.

194 is the highest individual cricket batting score achieved in a oneday international. Saeed Anwar from Pakistan scored it against India in Chennai in the 1996/97 season.

20 000

South Africans die every year owing to smoking. Fifty-two per cent of South African men and 17% of women smoke.

9,46 trillion (9 460 000 000 000) kilometres is the distance light travels in a single year.

36978 is the number to SMS to download the HIP2B2 mobizine to your phone. Include the code mobi HIP2B2 (the cost is R5).

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SMART TECHNOLOGY the science of everyday things

COOL DESK TOYS Acrobots and Acrobot Dragons are great desk toys that can be posed – because they have flexible joints – or stacked together – because they have magnets in their hands and feet. A very simple concept, but one that gives hours of fun.

Search for Acrobots on <www.thinkgeek.com> to see lots of photos that people have sent in of their own Acrobot poses, or buy your own Acrobot at <www.thegadgetshop.co.za>.

PERFECT PRINTING It’s late Sunday night. Your assignment is due on Monday morning and then your worst nightmare happens: your printer won’t work. Aaargh! To keep your printer in tip-top condition it helps to understand how an ink-jet printer works. Using a process called thermal ink-jet technology, the ink is heated very quickly by the printer to more than 300˚C. This creates a vapour bubble that expands and ejects a tiny drop of ink out of the chamber in the cartridge. The bubble then collapses, causing the chamber to fill itself again. If ink is contaminated with impurities it can clog the nozzle, which slows down this process. That’s why it’s good to keep your printer clean and free of dust, and why ink cartridges are such complicated, tightly sealed devices. FAST FACT

HP (Hewlett-Packard) invented thermal ink-jet technology in 1979. About 1 000 variations of an ink are tested by HP’s scientists before a specific formula is chosen.

RICE: THE NEW BRAIN FOOD Increase your vocabulary, become smarter and donate rice to help end world hunger – all with one click. Visit <www.freerice.com> and start playing the never-ending word quiz. You are given a word and four possible meanings. If you select the right answer you donate 10 grains of rice and the quiz starts to get harder. You can see how well you’re doing with the ‘vocab level’ rating and, over time, you’ll notice how you’re becoming a word pundit (expert). Of course, what we really want to know is who is sitting counting out all the grains of rice?

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SMART TECHNOLOGY

SAY IT WITH A SIGN Virtual technology has made it possible to have a sign-language interpreter in a room even when an interpreter isn’t available – it’s called SiSi (Say it Sign it). While someone speaks, the special software works out what the words are and then tells an animated avatar (see below) to sign the appropriate sign-language word, which is displayed on a screen. The technology can be adapted to work with any sign language, such as South African Sign Language. DID YOU KNOW?

An avatar is an icon or graphic – which can look like a person – that is used in a virtual world (such as a game) or an environment (such as with the SiSi technology) to represent something else.

BY MANDY J WATSON • PHOTOGRAPHS: ISTOCK PHOTOS

WORMS HARD AT WORK Instead of playing with dusty earthworms – or eating them, as is the custom in some places – you can use them to make an ecofriendly stinker. With an invention called Can-O-Worms you can make compost using special European earthworms (this is called vermiculture). TRY THIS AT HOME Place your vegetable waste in the top tray, put on the lid and the worms, who live in the second tray, will slowly convert the matter into organic compost, which forms in the bottom tray. You also get ‘worm tea’, a liquid fertiliser that forms in the process and that can be poured around plants. Once the bottom tray is full, tip the contents into your garden and then place the tray back on top of the stack and start the process all over again. Simple! For more, visit <www.fullcycle.co.za>. Cape Town has its own eeky display at the fancy Mount Nelson Hotel – home to the poshest earthworms around.

WHOSE IDEA WAS IT ANYWAY? Helen Bowyer, from IBM’s Hursley Emerging Technology Services in the UK, answers our questions about SiSi. Where did you get the idea from? Although I was learning BSL (British Sign Language), I was struggling to translate in meetings. Andy StanfordClark and another colleague had already spoken to the University of East Anglia about its avatar technology and a few of us got together to put the proposal together. How long did it take to develop the software and design the avatars? The avatars were designed by the University of East Anglia so I can’t comment on this, but the rest of the project was completed in 12 weeks. What equipment do you need to use SiSi? At the moment the system works on a laptop, although as it is built on IBM’s microbroker technology it could be extended to other devices, such as mobile phones. For laptop operation, you also need a microphone, a network connection and Java. Have deaf people tested it? How accurate and useful do they find it? It’s been developed and tested with a deaf user. The system is useful already, but the translation engine still needs further development in order to produce completely accurate BSL. The system’s accuracy is also dependent on having a good voice profile on the voice-recognition engine. How can the system be adapted for South African Sign Language (SASL) users? The system has been designed in a modular form. To add another language, two elements are needed: 1) a dictionary of SASL gestures; 2) an SASL translation module. Neither of these are trivial pieces of work but linking them into the SiSi architecture is relatively simple.

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DECONSTRUCTION

we take it apart

Analog joystick connects to potentiometers

Action buttons with symbols Motor with small weight generates countershock

Flexible conductive strip

Directional buttons

Potentiometers (variable resistors)

Connector sends instructions from the controller to the PS2 console box for processing

Motor with big unbalanced weight generates vibration Rigid plastic frame supports motor and electronics

DID YOU KNOW?

The PlayStation 2 is the best-selling game console in history, with over 120 million units sold as of 2007. That’s one for nearly every 50 people in the entire world.

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The PS2 controller essentially connects you to the game you want to play. The controller is designed to convert your physical actions (the movement of your hand) into precise mathematical data (usually in the form of ones and zeros) for the computer to understand. It consists of 15 buttons and two analog joysticks. HOW THE INDIVIDUAL COMPONENTS WORK Although every button has it own function, they all work on a similar principle. At the bottom of each button is a small curved disk. This disk is highly conductive. When you press down on any one of these buttons, it makes contact with a thin conductive strip mounted on the controller’s circuit board. The curved shape of the conductive disk allows for variation in the degree of conductivity. The harder you press the button, the more the curved conductive disk comes into contact with the thin conductive strip. The joysticks operate differently to the buttons. Below each joystick are two potentiometers, which are variable resistors, positioned perpendicularly to each other. Current flows constantly through each potentiometer. The amount of current is determined by the amount of resistance. Resistance is increased or decreased based on the position of the joystick. By monitoring the output of each potentiometer, the PS2 can determine the exact angle at which the joystick is being held, and trigger the appropriate response.

TEXT AND ILLUSTRATIONS: ANTHONY SAMBOER

THE INNER WORKINGS

1/7/08 9:37:25 AM


PS2 CONTROLLER Analog joystick

Top housing is made from tough ABS plastic

Front action buttons make contact with the adjacent contact pad when pressed

Flexible conductive strip Motors generate vibration

Soft rubber contact pads. The small curved discs are located underneath these buttons

Potentiometers (variable resistors)

OUR FAVOURITE BITS

Rigid plastic frame holds motor and electronics

The force feedback: this provides tactile stimulation to accompany certain Printed circuit board (PCB) actions – for example, in a racing game, you might feel a jarring vibration as your car slams into the wall. Force feedback is accomplished through the use of a very common device, a simple electric motor. In the Dual Shock 2 controller, two motors are used, one located in each handgrip. The shaft of each motor holds an unbalanced weight. When power is supplied to the motor, it spins the weight. Because the weight is Bottom casing supports motors unbalanced, the motor tries to wobble. But since it’s securely and electronic subassembly by mounted inside the controller, the wobble translates into a means of integrated ribs shuddering vibration of the controller itself.

SHOCK HORROR No more shock? What a horror. PS freaks will be sad to hear that Sony will no longer offer Dual Shock technology in their latest controllers.

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MENTALLY? Do you: sleep six to eight hours a night? read at least two books a month? do brain gym such as crosswords and sudoku regularly? have a positive attitude to life? avoid substances such as alcohol, cigarettes and drugs? carefully consider alternatives when making a decision?

PHYSICALLY? Do you: drink six to eight glasses of water every day? exercise for at least 20 minutes four times a week? participate in at least one type of sport? maintain a healthy weight? eat four or more portions of fruit and vegetables a day (a portion is about the size of your fist)? choose healthy options when ordering takeaways? B RAIN T H E R A P Y

Walking is not only good exercise, but it’s good for your brain too. It increases blood circulation which means more oxygen and glucose reaches your brain. Unlike strenuous exercise (like running or cycling), your legs don’t need extra glucose and oxygen when you walk, so your brain gets the full benefit and is oxygenated and refreshed – maybe this is why they say walking can ‘clear your head’.

New grade, new teachers, new opportunities, new challenges – have you got what it takes to make the most of the year ahead? (Tick the blocks that apply to you.)

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ECONOMICALLY? Do you: carefully manage the money you receive? think of creative ways to earn money? share or give money to others? spend thoughtfully and not impulsively? have a part-time job? invest some of your money wisely? FAST FACT

If you save R100 a month in a fixed-deposit account, you will earn more than R7 500 in five years.

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HEAD SMART

EMOTIONALLY? Do you: keep a journal of your feelings, thoughts and ideas? regularly share how you are feeling with someone? receive criticism without becoming defensive? take regular time just to be by yourself? better yourself by reading or learning new things? spend your time and energy on what is important to you?

STUDY TIP

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ACADEMICALLY?

When you learn something new, review the points that same day. This will cement the information in your brain so that at the next ‘official’ study session you will recognise it and find it easy to learn.

Do you: have an organised work space? have goals set for each of your subjects? think about ideas, not just memorise facts? use only study methods that work for you? have a study schedule that you stick to? seek ways to better your grades, like joining a study group?

BY MICHELLE MINNAAR PHOTOGRAPH: iSTOCK PHOTOS

HOW DID YOU SCORE? Add up the number of ticks in each category. 0–2: This seems like a weak area, but it is never too late! Make a list of ways to improve and set goals for the year ahead. Success is all about attitude. 3–4: Not too bad – but watch out for those items you didn’t tick. Increase your score in this category by focusing on the points that you lacked. Find ways to bring these things into your life. 5–6: Well done! You are ready for the year ahead! Keep finding ways to improve and remember to stay focused on your goals. HAVE A GREAT YEAR!

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SIMPLE TRUTHS

Ever wondered why elephants walk so

quietly? Or why old chocolate goes white? Or why the sea is salty when rivers are fresh, or why there are 26 letters in the alphabet, or why people can walk on beds of hot coals without burning their feet, or why shower curtains are attracted to wet bodies? Or, more importantly, why you’re reading this when the answers are waiting for you just over the page?

Oh, and as for the quiet elephant – scientists believe it has to do with the structure of its foot. Apart from having big feet to support its weight, there is also a large fatty cushion under each foot. This acts as a kind of shock absorber, and also lifts the foot bones near the heel off the ground, allowing an elephant to walk almost on its toes. Heavy stuff!

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Why is the sea salty when rivers are fresh?

Crust

geological techniques and satellite images, that we learned that land covers only about a third of the globe’s surface. And that’s an important distinction. The land mass and oceans form only the outer skin of the globe. Beneath this pretty face lies close to another 6 400 km of Earth, which can be divided into three layers based on different physical characteristics. Moving from the surface inwards, these are called the crust, mantle and core. Continents and the ocean floor together form quite a rigid, solid crust, while the upper part of the mantle is more flexible because of lots of almost molten rocks. The crust thus actually floats on a thick layer of dense, gooey stuff. But not to worry, with 35 km of solid crust between us and the flexible part of the mantle, we have our feet firmly on the ground. Mantle

We dug into the archives and found that the word ‘earth’ originates from the medieval German word ‘erde’, meaning soil or ground. Prof. Terence McCarthy of the School of Geosciences at Wits University explains, ‘Unlike the big gas planets like Jupiter and Saturn, Earth is a rocky planet. Exposing rock to a combination of oxygen and water in a slightly acidic environment over many years will gradually let it break down to soil.’ So we can forgive the folks back in the Middle Ages for thinking that ‘earth’ aptly described their planet. It was only much later, with sophisticated

Core

Why is the earth not called water when it is 70% water?

Got a question buzzing in your head? Add your own ‘Why?’ question to the Forum at <www.hip2b2.com>.

The salt in the sea comes from the breakdown of rocks on the ocean floor, as well as rocks on the land. The minerals get washed down into the sea and have accumulated there as salts. The rivers are fresh because that water comes from rain, which comes from water that is evaporated from the sea. When water evaporates, it leaves the salts behind (think of the salt that stays behind when your sea-soaked bathing costume dries). So the salts stay in the sea while the water moves round in the water cycle.

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SIMPLE TRUTHS

Why do we call it a shooting star when it doesn’t come from a star? Quite simply because it looks like a star whizzing through the sky. Meteors, not to be confused with meteorites, are small bits of rock or metal that burst into flaming gas as they enter the Earth’s atmosphere. Moving at about 100 000 km/h, the only clue of the lightning-fast crash is a faint, momentary streak in the sky. Dr Claire Flanagan, astronomer and director of the Johannesburg Planetarium says: ‘Think of the atmosphere as the Earth’s windscreen. Meteors are like little bugs crashing into it at high speed, leaving only a bright trace to show that they were there.’ Enlightening.

Meteor: falls through atmosphere Meteorite: lands on earth Meteoroid: space debris

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Why can we walk on hot coals without burning our feet? BY MARK VAN DIJK PROF ALISON LEWIS LINDA PRETORIUS PAUL CARTER

This has to do with two things: the thermal conductivity (how easily heat flows) and the heat capacity (the amount of heat required to increase an object’s temperature by one DID degree) of the soles of feet. The thermal conductivity of YOU KNOW? feet is quite low, so the movement of heat from the Until 1774, scientists coals to the feet happens relatively slowly. (This is thought heat was due to the also why you can touch a hot pot for a fraction of release (during combustion) of a second and not get burnt.) And since the soles an invisible substance called of our feet are mostly water, their heat capacity is phlogiston from materials like essentially that of water, which is relatively high. wood and coal. This means they can absorb quite a lot of heat before their temperature rises significantly. Physics may make it possible, but firewalking can be dangerous if not performed carefully. In 2002, 20 Australian KFC managers received treatment for burns caused by firewalking at a leadership conference.

Why does my tummy rumble when I’m hungry? You’re writing exams and the hall is really quiet. Then all of a sudden your tummy starts rumbling, and everyone can hear. It’s embarrassing! Knowing that it is a completely natural occurrence may offer some consolation. Tummy rumbles are also known as borborygmi and are caused by muscle contractions of the stomach and small intestines. Once muscle contractions of the stomach have punched food to a pulp, the pulp is released into the small intestines. Further digestion also forms a bit of gas. As alternative cycles of muscle contractions and relaxation propel liquid and gas pockets through the intestines, gurgling sounds arise. By the time you get hungry, the previous digestion process is almost complete and as the last of the contents are squeezed through the rumbling gets a bit louder. SHOCK HORROR

On average, a person produces about half a litre of fart gas per day, distributed over an average of about 14 daily farts.

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SIMPLE TRUTHS

BY MARK VAN DIJK, PROF ALISON LEWIS, LINDA PRETORIUS, PAUL CARTER, NICKLAUS KRUGER ∙ PHOTOGRAPHS: iSTOCK PHOTOS, GALLO/GETTYIMAGES.COM

Why do I leak when I cry? You won’t usually cry over spilt milk – unless it has ruined your outfit just before your date with some hottie. Increased stimulation of a small gland just above the outer ends of our eyes lets more tears flow into the eye than usual. When these can’t drain fast enough, tears spill over your eyelids. The gland’s stimulation is likely controlled by combined action of the hormonal, nervous and immune systems. Since tears also contain feel-good neurotransmitters, scientists think emotional tears help us deal with stress and pain.

And why do I smile? Smiling is linked to positive emotions like happiness and enjoyment. When you feel truly happy, the emotional part of your brain sends signals to brain areas controlling facial muscle contractions. The muscles between the mouth corners and cheeks, as well as those around the eye, subsequently contract.

Why are some people born with tails? Your mother might have called you a monkey even though you don’t have a tail but some people really are born with them. It’s a very rare condition, but still, there are over a hundred cases of human tails documented in medical literature. There are two main types of human tails: pseudotails are lesions or deformities in the FAST FACT caudal (lower spine) region; true tails, on the other hand, According to are characterised by connective tissue, blood vessels, <www.myspace.com>, nerve fibres – everything you’d find in a spine, if it were 229 mm is the length of the longest human tail on record, which just a little bit longer. belonged to a 12-year-old boy The true human tail is a rather good example of what who lived in French Indochina, scientists call an evolutionary atavism. Atavism is the which was part of the French reappearance of a trait that had disappeared generations colonial empire in Asia. ago. Human embryos grow tails, because our vertebrate ancestry once included a tailed stage, and our developmental plan still does, even though it normally gets reabsorbed long before birth. Genetic mistakes can cause this absorption stage to malfunction … and, voila, you have a baby with a tail.

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Why does old chocolate go white?

Why are shower curtains attracted to wet bodies? It never fails. Get into the shower, turn on the water, relax … then suddenly you’re under attack! Most scientists think this has to do with a buoyancy effect – hot air rises, and this might produce a pressure difference that could cause the air in your shower to move the curtain. But the curtain is out to get you even when you take a cold shower, so this explanation won’t do. The real explanation was discovered by David Smith, an assistant professor at the University of Massachusetts, who devised a fluid dynamics* computer simulation of it. What happens is that the water stream displaces the air as it falls, creating a vortex of air that rotates horizontally. The eye (centre) of the vortex is at a lower pressure than the rest, which causes air to move in towards it from the surrounding regions – and so sucks the curtain right onto you. Next time your shower curtain attacks you, remember it’s nothing personal – it’s just science.

Cocoa butter, the main solid fat in chocolate, can crystallise and assume a crystalline form into six different arrangements of molecules known as polymorphs. The dominant polymorph in the best-tasting chocolate is the beta-V form. This polymorph makes the chocolate look glossy and melt in the mouth. If the chocolate is old or has not been stored properly, the beta-V polymorph (or arrangement) changes into the more stable beta-VI polymorph. It is this that causes the white ‘mouldy’ appearance on the chocolate. But don’t toss out your yummy treat: the chocolate is still perfectly safe to eat, although it is not quite as yummy.

Alpha conformation

Beta conformation

DID YOU KNOW?

Because the beta-V polymorph of cocoa butter has a melting point slightly lower than body temperature, it is used by pharmaceutical companies to prepare suppositories (tablets inserted through your anus). A suppository is made by mixing the medication with cocoa butter. As the cocoa butter melts away, the drug is gradually released.

*Fluid dynamics is the study of fluids (liquids and gases in motion). Shower curtain

Air current flowing upward

For more wacky science, visit <www.null-hypothesis.co.uk>, the website of The Journal of Unlikely Science.

Crystalline: a solid substance in which the constituent atoms, molecules or ions are packed in a regularly ordered, repeating pattern extending in all three spatial dimensions. Ice is crystalline. Polymorph: a crystalline substance in which the same molecules can be organised in a number of different arrangements. In the diagrams above, which show the alpha and beta polymorphs of L-glutamic acid, the molecules are exactly the same, but their arrangement is different.

18

why.indd 6

1/8/08 10:18:23 AM


SIMPLE TRUTHS Segment

Why are there Circumscribed circle 360º in a circle? For many things we want to know the answer to there is no special reason. There are 360º in a circle mostly just as a matter of choice. So when did the choice happen? History dates it back to the Babylonians, who lived in present-day Iraq at about 2 000 BC. The Babylonians used a hexadecimal system of counting. This means that they counted in multiples of 60. (We use a denary system: multiples of 10.) The Babylonians were extremely advanced

Radius

(it is believed they were the first people to develop a system of writing) and they were fond of geometry. They noticed that a regular hexagon had a circumference equal to six times the radius of its circumscribed circle (the circle that just fits around it). They saw, therefore, that a circle could be divided into six equal segments. Because they counted Hexagon circumference in multiples of 60, each segment was divided into 60 parts, giving an equation of 6 x 60 = 360 parts altogether. The amount of rotation in each of these parts came to be called a degree, thereby giving 360º to the circle.

Why do computers use binary? Perhaps we should ask what binary is first. Binary is a counting system that uses only the numbers 0 and 1, and counts in powers of 2. The decimal system (which we use every day) uses the numbers 0 to 9, and counts in powers of 10. Look at the way that the number 13 is written in the two systems: BINARY

Eights 1

DECIMAL SYSTEM

Fours

Twos 1

Ones 0

=1×8+1×4+0×2+1×1 = 13

Hundreds Tens

Units 1

1

3

= 1 × 10 + 3 × 1 = 13

The binary system seems much longer, so why would computers use it? It all comes down to how computers work: they run on electricity. The digital circuits in the chips of computers switch electricity on and off very quickly. The circuits use ‘on’ as a signal for 1 and ‘off’ as a signal for 0. Using billions of different combinations of these signals, computers can perform all their tasks. This should give you an idea of just how quickly they work.

19

why.indd 7

1/8/08 10:18:49 AM


SIMPLE TRUTHS

Why are there no more unicorns? A few centuries ago, they seemed to be everywhere – magnificent horses with a single horn projecting from their heads. But where have all the unicorns gone? The short answer: there never were any. The reason people thought there were seems to lie with ancient sailors, who would bring home tales from faraway lands of barelyglimpsed animals that seemed strange and fantastic – but rarely matched up to reality. Dr Chris Rowan, a geologist at Wits University, says there is no fossil evidence of unicorns ever having existed, except for the single unicorn skeleton reconstructed from prehistoric bones by Otto von Guericke in 1663. It convinced the philosopher Gottfried Leibniz, but others were skeptical, and the skeleton was scattered and is

Why is ‘gh’ pronounced ‘ff’ in English? SPELLING TESTS ARE REALLY TOUGH. WHO KNOWS HOW TO SPELL THIS STUFF? TAKE FOR EXAMPLE A WORD LIKE ‘COUGH’. COMMON SENSE TELLS YOU TO JUST SPELL IT ‘KOFF’. BECAUSE THAT’S HOW IT SOUNDS! ALTHOUGH … YOU KNOW THAT THAT’S NOT RIGHT. SO … YOU START PAGING THROUGH A DICTIONARY TO SEE WHAT TO DO. THERE WE LEARN ‘COUGH’ CAME FROM THE OLD ENGLISH ‘COGHEN’ WHERE ‘GH’ WAS SAID ‘FF’ (THE WORD RHYMED WITH ‘BOFFIN’). AND ALSO, THE OLD ENGLISH ‘DAG’ BECAME ‘DOUGH’ AND ‘TOUGH’ CAME FROM ‘TOH’, AND ‘ENOUGH’ FROM ‘ENOW’. YOU SEE, ‘GH’ CAN EITHER BE SILENT OR ROUGH AND THAT CAN MAKE SPELLING WORDS TOUGH ’COS IT JUST SEEMS SO CRAZY THAT ‘TOUGH’, ‘COUGH’ AND ‘BOUGH’ ARE SPELLED THE SAME WAY AS ‘ROUGH’, ‘TROUGH’ AND ‘PLOUGH’. SO, YOU KNOW … HERE’S A THOUGHT: SOMEONE REALLY JUST OUGHT TO SPELL ‘COUGH’ ‘KOFF’, AND THEN SHOUT: ‘ENOUGH! I’M THOROUGHLY TIRED OF MISSPELLING STUFF!’

now lost to us. Zoology professor Lincoln Raitt of UWC agrees. ‘Unicorns seem to have been a mythical creature based on the side view of the Arabian oryx, close relative of our gemsbok.’ The oryx was not alone: many animals may have added to the unicorn myth. The rhinoceros is the most obvious inspiration: it has the horn, and rhinoceroses are closely related to horses. The narwhal, an ocean-dwelling mammal, has a long horn that looks very much like a unicorn horn. Goats with rare tissue deformities sometimes have their horns joined together. But none of these fit the classical definition of unicorns. As biologists learnt more about the world’s animals, there just didn’t seem to be a place for unicorns. Science killed the unicorn, but it did it with kindness.

Why are there 26 letters in our alphabet? Our alphabet is based on the Latin alphabet, which was a redesigned form of Etruscan, which was a tweak on Greek, which was based on Phoenician, which in turn was based on the 23 glyphs (each of which represented a unique sound) of the Proto-Canaanite alphabet, which is the great-great-granddaddy of many modern alphabets, ranging from Arabic to Greek to Hebrew and even Thai. The letters changed over the centuries, but by 500 BC Latin had a 21-letter alphabet that looked almost exactly like ours … except theirs didn’t have G, J, U, W, Y or Z. Around 300 BC the Romans (who spoke Latin) added G, Y and Z to help them spell out certain Greek sounds. W came in the 1300s when the Anglo-Saxons started using the Latin alphabet; J (a breakaway from I) came in the 1600s; and U (from V) came in the 1800s … and there’s our 26-letter alphabet.

FAST FACT

While the Latin alphabet has 26 letters, many others don’t. Greek has 24 letters; Arabic has 28; and the Chinese alphabet has 47 035 characters.

20

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1/8/08 10:18:59 AM


why.indd 9

1/8/08 10:19:03 AM


Why is the sea salty when rivers are fresh?

Crust

geological techniques and satellite images, that we learned that land covers only about a third of the globe’s surface. And that’s an important distinction. The land mass and oceans form only the outer skin of the globe. Beneath this pretty face lies close to another 6 400 km of Earth, which can be divided into three layers based on different physical characteristics. Moving from the surface inwards, these are called the crust, mantle and core. Continents and the ocean floor together form quite a rigid, solid crust, while the upper part of the mantle is more flexible because of lots of almost molten rocks. The crust thus actually floats on a thick layer of dense, gooey stuff. But not to worry, with 35 km of solid crust between us and the flexible part of the mantle, we have our feet firmly on the ground. Mantle

We dug into the archives and found that the word ‘earth’ originates from the medieval German word ‘erde’, meaning soil or ground. Prof. Terence McCarthy of the School of Geosciences at Wits University explains, ‘Unlike the big gas planets like Jupiter and Saturn, Earth is a rocky planet. Exposing rock to a combination of oxygen and water in a slightly acidic environment over many years will gradually let it break down to soil.’ So we can forgive the folks back in the Middle Ages for thinking that ‘earth’ aptly described their planet. It was only much later, with sophisticated

Core

Why is the earth not called water when it is 70% water?

Got a question buzzing in your head? Add your own ‘Why?’ question to the Forum at <www.hip2b2.com>.

The salt in the sea comes from the breakdown of rocks on the ocean floor, as well as rocks on the land. The minerals get washed down into the sea and have accumulated there as salts. The rivers are fresh because that water comes from rain, which comes from water that is evaporated from the sea. When water evaporates, it leaves the salts behind (think of the salt that stays behind when your sea-soaked bathing costume dries). So the salts stay in the sea while the water moves round in the water cycle.

14

why.indd 2

1/8/08 10:19:42 AM


SIMPLE TRUTHS

Why do we call it a shooting star when it doesn’t come from a star? Quite simply because it looks like a star whizzing through the sky. Meteors, not to be confused with meteorites, are small bits of rock or metal that burst into flaming gas as they enter the Earth’s atmosphere. Moving at about 100 000 km/h, the only clue of the lightning-fast crash is a faint, momentary streak in the sky. Dr Claire Flanagan, astronomer and director of the Johannesburg Planetarium says: ‘Think of the atmosphere as the Earth’s windscreen. Meteors are like little bugs crashing into it at high speed, leaving only a bright trace to show that they were there.’ Enlightening.

Meteor: falls through atmosphere Meteorite: lands on earth Meteoroid: space debris

15

why.indd 3

1/8/08 10:19:55 AM


Why can we walk on hot coals without burning our feet? BY MARK VAN DIJK PROF ALISON LEWIS LINDA PRETORIUS PAUL CARTER

This has to do with two things: the thermal conductivity (how easily heat flows) and the heat capacity (the amount of heat required to increase an object’s temperature by one DID degree) of the soles of feet. The thermal conductivity of YOU KNOW? feet is quite low, so the movement of heat from the Until 1774, scientists coals to the feet happens relatively slowly. (This is thought heat was due to the also why you can touch a hot pot for a fraction of release (during combustion) of a second and not get burnt.) And since the soles an invisible substance called of our feet are mostly water, their heat capacity is phlogiston from materials like essentially that of water, which is relatively high. wood and coal. This means they can absorb quite a lot of heat before their temperature rises significantly. Physics may make it possible, but firewalking can be dangerous if not performed carefully. In 2002, 20 Australian KFC managers received treatment for burns caused by firewalking at a leadership conference.

Why does my tummy rumble when I’m hungry? You’re writing exams and the hall is really quiet. Then all of a sudden your tummy starts rumbling, and everyone can hear. It’s embarrassing! Knowing that it is a completely natural occurrence may offer some consolation. Tummy rumbles are also known as borborygmi and are caused by muscle contractions of the stomach and small intestines. Once muscle contractions of the stomach have punched food to a pulp, the pulp is released into the small intestines. Further digestion also forms a bit of gas. As alternative cycles of muscle contractions and relaxation propel liquid and gas pockets through the intestines, gurgling sounds arise. By the time you get hungry, the previous digestion process is almost complete and as the last of the contents are squeezed through the rumbling gets a bit louder. SHOCK HORROR

On average, a person produces about half a litre of fart gas per day, distributed over an average of about 14 daily farts.

16 14

why.indd 4

1/8/08 10:20:37 AM


SIMPLE TRUTHS

BY MARK VAN DIJK, PROF ALISON LEWIS, LINDA PRETORIUS, PAUL CARTER, NICKLAUS KRUGER ∙ PHOTOGRAPHS: iSTOCK PHOTOS, GALLO/GETTYIMAGES.COM

Why do I leak when I cry? You won’t usually cry over spilt milk – unless it has ruined your outfit just before your date with some hottie. Increased stimulation of a small gland just above the outer ends of our eyes lets more tears flow into the eye than usual. When these can’t drain fast enough, tears spill over your eyelids. The gland’s stimulation is likely controlled by combined action of the hormonal, nervous and immune systems. Since tears also contain feel-good neurotransmitters, scientists think emotional tears help us deal with stress and pain.

And why do I smile? Smiling is linked to positive emotions like happiness and enjoyment. When you feel truly happy, the emotional part of your brain sends signals to brain areas controlling facial muscle contractions. The muscles between the mouth corners and cheeks, as well as those around the eye, subsequently contract.

Why are some people born with tails? Your mother might have called you a monkey even though you don’t have a tail but some people really are born with them. It’s a very rare condition, but still, there are over a hundred cases of human tails documented in medical literature. There are two main types of human tails: pseudotails are lesions or deformities in the FAST FACT caudal (lower spine) region; true tails, on the other hand, According to are characterised by connective tissue, blood vessels, <www.myspace.com>, nerve fibres – everything you’d find in a spine, if it were 229 mm is the length of the longest human tail on record, which just a little bit longer. belonged to a 12-year-old boy The true human tail is a rather good example of what who lived in French Indochina, scientists call an evolutionary atavism. Atavism is the which was part of the French reappearance of a trait that had disappeared generations colonial empire in Asia. ago. Human embryos grow tails, because our vertebrate ancestry once included a tailed stage, and our developmental plan still does, even though it normally gets reabsorbed long before birth. Genetic mistakes can cause this absorption stage to malfunction … and, voila, you have a baby with a tail.

17

why.indd 5

1/8/08 10:20:50 AM


Why does old chocolate go white?

Why are shower curtains attracted to wet bodies? It never fails. Get into the shower, turn on the water, relax … then suddenly you’re under attack! Most scientists think this has to do with a buoyancy effect – hot air rises, and this might produce a pressure difference that could cause the air in your shower to move the curtain. But the curtain is out to get you even when you take a cold shower, so this explanation won’t do. The real explanation was discovered by David Smith, an assistant professor at the University of Massachusetts, who devised a fluid dynamics* computer simulation of it. What happens is that the water stream displaces the air as it falls, creating a vortex of air that rotates horizontally. The eye (centre) of the vortex is at a lower pressure than the rest, which causes air to move in towards it from the surrounding regions – and so sucks the curtain right onto you. Next time your shower curtain attacks you, remember it’s nothing personal – it’s just science.

Cocoa butter, the main solid fat in chocolate, can crystallise and assume a crystalline form into six different arrangements of molecules known as polymorphs. The dominant polymorph in the best-tasting chocolate is the beta-V form. This polymorph makes the chocolate look glossy and melt in the mouth. If the chocolate is old or has not been stored properly, the beta-V polymorph (or arrangement) changes into the more stable beta-VI polymorph. It is this that causes the white ‘mouldy’ appearance on the chocolate. But don’t toss out your yummy treat: the chocolate is still perfectly safe to eat, although it is not quite as yummy.

Alpha conformation

Beta conformation

DID YOU KNOW?

Because the beta-V polymorph of cocoa butter has a melting point slightly lower than body temperature, it is used by pharmaceutical companies to prepare suppositories (tablets inserted through your anus). A suppository is made by mixing the medication with cocoa butter. As the cocoa butter melts away, the drug is gradually released.

*Fluid dynamics is the study of fluids (liquids and gases in motion). Shower curtain

Air current flowing upward

For more wacky science, visit <www.null-hypothesis.co.uk>, the website of The Journal of Unlikely Science.

Crystalline: a solid substance in which the constituent atoms, molecules or ions are packed in a regularly ordered, repeating pattern extending in all three spatial dimensions. Ice is crystalline. Polymorph: a crystalline substance in which the same molecules can be organised in a number of different arrangements. In the diagrams above, which show the alpha and beta polymorphs of L-glutamic acid, the molecules are exactly the same, but their arrangement is different.

18

why.indd 6

1/8/08 10:21:06 AM


SIMPLE TRUTHS Segment

Why are there Circumscribed circle 360º in a circle? For many things we want to know the answer to there is no special reason. There are 360º in a circle mostly just as a matter of choice. So when did the choice happen? History dates it back to the Babylonians, who lived in present-day Iraq at about 2 000 BC. The Babylonians used a hexadecimal system of counting. This means that they counted in multiples of 60. (We use a denary system: multiples of 10.) The Babylonians were extremely advanced

Radius

(it is believed they were the first people to develop a system of writing) and they were fond of geometry. They noticed that a regular hexagon had a circumference equal to six times the radius of its circumscribed circle (the circle that just fits around it). They saw, therefore, that a circle could be divided into six equal segments. Because they counted Hexagon circumference in multiples of 60, each segment was divided into 60 parts, giving an equation of 6 x 60 = 360 parts altogether. The amount of rotation in each of these parts came to be called a degree, thereby giving 360º to the circle.

Why do computers use binary? Perhaps we should ask what binary is first. Binary is a counting system that uses only the numbers 0 and 1, and counts in powers of 2. The decimal system (which we use every day) uses the numbers 0 to 9, and counts in powers of 10. Look at the way that the number 13 is written in the two systems: BINARY

Eights 1

DECIMAL SYSTEM

Fours

Twos 1

Ones 0

=1×8+1×4+0×2+1×1 = 13

Hundreds Tens

Units 1

1

3

= 1 × 10 + 3 × 1 = 13

The binary system seems much longer, so why would computers use it? It all comes down to how computers work: they run on electricity. The digital circuits in the chips of computers switch electricity on and off very quickly. The circuits use ‘on’ as a signal for 1 and ‘off’ as a signal for 0. Using billions of different combinations of these signals, computers can perform all their tasks. This should give you an idea of just how quickly they work.

19

why.indd 7

1/8/08 10:21:27 AM


Why are there no more unicorns? A few centuries ago, they seemed to be everywhere – magnificent horses with a single horn projecting from their heads. But where have all the unicorns gone? The short answer: there never were any. The reason people thought there were seems to lie with ancient sailors, who would bring home tales from faraway lands of barelyglimpsed animals that seemed strange and fantastic – but rarely matched up to reality. Dr Chris Rowan, a geologist at Wits University, says there is no fossil evidence of unicorns ever having existed, except for the single unicorn skeleton reconstructed from prehistoric bones by Otto von Guericke in 1663. It convinced the philosopher Gottfried Leibniz, but others were skeptical, and the skeleton was scattered and is

Why is ‘gh’ pronounced ‘ff’ in English? SPELLING TESTS ARE REALLY TOUGH. WHO KNOWS HOW TO SPELL THIS STUFF? TAKE FOR EXAMPLE A WORD LIKE ‘COUGH’. COMMON SENSE TELLS YOU TO JUST SPELL IT ‘KOFF’. BECAUSE THAT’S HOW IT SOUNDS! ALTHOUGH … YOU KNOW THAT THAT’S NOT RIGHT. SO … YOU START PAGING THROUGH A DICTIONARY TO SEE WHAT TO DO. THERE WE LEARN ‘COUGH’ CAME FROM THE OLD ENGLISH ‘COGHEN’ WHERE ‘GH’ WAS SAID ‘FF’ (THE WORD RHYMED WITH ‘BOFFIN’). AND ALSO, THE OLD ENGLISH ‘DAG’ BECAME ‘DOUGH’ AND ‘TOUGH’ CAME FROM ‘TOH’, AND ‘ENOUGH’ FROM ‘ENOW’. YOU SEE, ‘GH’ CAN EITHER BE SILENT OR ROUGH AND THAT CAN MAKE SPELLING WORDS TOUGH ’COS IT JUST SEEMS SO CRAZY THAT ‘TOUGH’, ‘COUGH’ AND ‘BOUGH’ ARE SPELLED THE SAME WAY AS ‘ROUGH’, ‘TROUGH’ AND ‘PLOUGH’. SO, YOU KNOW … HERE’S A THOUGHT: SOMEONE REALLY JUST OUGHT TO SPELL ‘COUGH’ ‘KOFF’, AND THEN SHOUT: ‘ENOUGH! I’M THOROUGHLY TIRED OF MISSPELLING STUFF!’

now lost to us. Zoology professor Lincoln Raitt of UWC agrees. ‘Unicorns seem to have been a mythical creature based on the side view of the Arabian oryx, close relative of our gemsbok.’ The oryx was not alone: many animals may have added to the unicorn myth. The rhinoceros is the most obvious inspiration: it has the horn, and rhinoceroses are closely related to horses. The narwhal, an ocean-dwelling mammal, has a long horn that looks very much like a unicorn horn. Goats with rare tissue deformities sometimes have their horns joined together. But none of these fit the classical definition of unicorns. As biologists learnt more about the world’s animals, there just didn’t seem to be a place for unicorns. Science killed the unicorn, but it did it with kindness.

POEM BY MARK VAN DIJK

SIMPLE TRUTHS

Why are there 26 letters in our alphabet? Our alphabet is based on the Latin alphabet, which was a redesigned form of Etruscan, which was a tweak on Greek, which was based on Phoenician, which in turn was based on the 23 glyphs (each of which represented a unique sound) of the Proto-Canaanite alphabet, which is the great-great-granddaddy of many modern alphabets, ranging from Arabic to Greek to Hebrew and even Thai. The letters changed over the centuries, but by 500 BC Latin had a 21-letter alphabet that looked almost exactly like ours … except theirs didn’t have G, J, U, W, Y or Z. Around 300 BC the Romans (who spoke Latin) added G, Y and Z to help them spell out certain Greek sounds. W came in the 1300s when the Anglo-Saxons started using the Latin alphabet; J (a breakaway from I) came in the 1600s; and U (from V) came in the 1800s … and there’s our 26-letter alphabet.

FAST FACT

While the Latin alphabet has 26 letters, many others don’t. Greek has 24 letters; Arabic has 28; and the Chinese alphabet has 47 035 characters.

20

why.indd 8

1/8/08 1:56:43 PM


DOGBREATH, YELLOW TEETH, UGLY SKIN … AND MORE DISGUSTING REASONS

BY MARK VAN DIJK • PHOTOGRAPHS: iSTOCK PHOTOS, GALLO/GETTYIMAGES.

WHY SMOKING IS A DUMB IDEA

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bodysmart1.indd 2

1/7/08 9:57:31 AM


BODY SMART

BRAI N DRA I N Smoking makes you stupid … and science proves it. Cigarette smoke contains 4 000 toxins – of which nicotine is just one. In 2002 French researchers exposed a group of lab rats to high doses of nicotine; these rats suffered a 50% greater loss of new brain cells than the control group of rats that hadn’t been exposed to nicotine. If it does that to rats, imagine what it can do to you! So if you want to keep your brain in peak condition, don’t smoke.

FADI N G E YES I G H T

Then when the smoke reaches your lungs, it effects mucus secretion and makes that coughing – gwaak-gwaark-gwaahrm! – even worse. No wonder smoking is linked to more than 80% of all lung-cancer and bronchialdisease deaths.

UGLY BETTY In 1985, Dr Douglas Model of Eastbourne, England, surveyed 116 smokers and found that they suffered from a condition he called ‘smoker’s face’. What happens is that the toxins (all 4 000 of them) in cigarette smoke cause inflammation across your entire body, making your skin look like a rough, wrinkly old prune.

B R O K EN-H EA RTED Smoking triples your risk of heart disease and heart attack, and doubles your risk of a stroke. And more than half of the people who die because of smoking die in middle age – cutting two decades off their life expectancy. Oh, and smoking is also responsible for 30% of all heart attacks and cardiovascular deaths. You do the maths …

S TO M A C H B U G

Smoking speeds up the development of macular degeneration, an eye condition (usually found in the elderly) that causes blindness. This is what happens: smoking stiffens the walls of your arteries and causes fats to clog them … and the arteries that supply blood to the macular region of your eyes’ retinas are among the narrowest in your body – which is why they’re the first to suffer.

A muscular valve at the bottom of the oesophagus (gullet) prevents stomach acids entering the oesophagus. But smoking weakens this valve, letting those stomach acids flow back into your oesophagus and giving you heartburn. And if you’re still keeping score, smoking also damages your kidneys and increases your risk of bladder and pancreatic cancer, thanks to all those cancer-causing chemicals.

F OUL M OUT H

(U N)R EP R O D U C TIV E ORGANS

Because it contains cancer-causing chemicals (including nicotine, carbon monoxide, formaldehyde, arsenic and acetone), smoking drastically increases your risk of developing cancer of the mouth, tongue and throat. But first it’ll reduce the delivery of oxygen and nutrients to your gums, giving you periodontal (gum) disease and halitosis (stinky breath). And your teeth will become yellow and rotten as the chemicals contained in tobacco smoke generate a type of calcium that makes it easier for plaque to stick to your teeth.

Smoking reduces women’s fertility, speeds up the onset of menopause, increases the risk of cervical cancer and leads to irregular menstrual cycles. And it’s no good for men, either: smoking leads to a lower sperm count, a higher percentage of deformed sperm and an increase in impotence. Cigarette smoke releases nearly 4 000 chemicals into your lungs, including nicotine and tar, which blacken and weaken them – and the extra mucus produced in smokers’ lungs slows down the cilia that clean them, making matters worse. DID YOU KNOW?

AL L CHOKE D U P Smoking pumps poisons like hydrogen cyanide through your bronchi (breathing tubes), which makes them inflamed, leading to the infamous gwaak-gwaark! smoker’s cough.

When you quit smoking your body can slowly start to repair itself. If you haven’t yet contracted a smoking-related disease, your body could return to normal within 15 years of stubbing out that last cig.

STUMPED Because it causes your arteries to clog up, smoking can also reduce supplies of fresh oxygen being carried around your body. This condition, known as peripheral vascular disease, eventually makes you unable to feel your fingers or toes, leading to chronic pain and possibly the formation of gangrene (cell decay). And then you’ll have to have your feet amputated.

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bodysmart1.indd 3

1/7/08 9:41:03 AM


sala kuhle ikhomphyutha kubayini? ukuhleba

isiNdebele (S. Ndebele)

totsiens rekenaar hoekom? skinder

Afrikaans

goodbye computer why? gossip

South African English

sala kahle khomphyuta hikokwalaho ka yini? ku hleva

Xitsonga (Tsonga)

sala kakuhle ikhompyutha kutheni? ukuhleba

isiXhosa (Xhosa)

sala kahle ngcondvomshini kungani? kuhleba

Siswati (Swati)

Communicate in our 11 official languages hello hallo lotjha

sawubona molo avuxeni

centrefold.indd 2 1/7/08 9:42:08 AM


thobela dumela dumela

sala sentle khomphuta ka ntlha yang? go seba

Setswana (Tswana)

sala hantle khomputa ho baneng? ho seba

kha vha sale zwavhudi ˆ khomphiyutha Ndi ngani? u sola

Tshivenda (Venda)

sala kahle ikhompiyutha kungani? ukuhleba

isiZulu (Zulu)

think. what you can be

Sesotho (Sotho/S. Sotho)

sala gabotse khomphutha goreng? go seba

sawubona ndi matsheloni

Sesotho sa Leboa (N. Sotho) ˆ

centrefold.indd 3 1/7/08 9:42:22 AM

TRANSLATIONS PROVIDED BY TRANSLATION WORLD


SCI DIY

The speed oflight Fancy yourself a physicist? Measure the speed of light using a microwave … and chocolate. (You can eat your experiment afterwards.) WHAT YOU NEED • a slab of chocolate (at least 18 cm by 8 cm)

• a microwave • a paper towel • a plate • a ruler (or tape measure) • toothpicks HOW TO DO IT

1 Check the microwave to determine the frequency at which it functions. (Most microwaves operate at 2,45 GHz*, but it’s best to check for the sign marked RF.) 2 Disable or remove the rotating turntable on the microwave. (If necessary, place a bowl over the tiny rotator mechanism, or unscrew it if you’re feeling destructive.) 3 Place the chocolate – with the packaging removed, of course! – on the paper towel, and place them both on the plate. 4 Place the plate in the microwave, so that the chocolate is positioned with the longest sides facing the longest sides of the microwave. 5 Heat the chocolate until it barely begins to melt, pausing the oven to check occasionally (the time required will vary with the oven, from 20–90 seconds). 6 Once the chocolate has begun to melt, remove it from the microwave and probe the surface for a pattern of hot melted spots. 7 Use toothpicks to mark the centre of each hot spot. 8 Measure the distance between the toothpicks**, and plug it into the equation below.

wavelength** (in metres) x frequency (in Hertz) = speed of light (in metres/second) *1 GHz = 1 000 MHz = 1 000 000 000 Hz (Hertz) **wavelength = 2 x distance between toothpicks HOW DOES IT WORK?

The wavelength, frequency and speed of light (and other kinds of electromagnetic emissions, like microwaves) are all closely related. The standing waves in the microwave oven create a pattern of hot spots where the microwave enters and leaves the chocolate and so causes more atomic motion. The distance between two hot spots is half a wavelength. So once you have the wavelength and the frequency, you’re ready to work out the speed of light.

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1/7/08 9:44:00 AM


ADVERTORIAL

RESEARCH & EXPERIMENT CONDUCTED BY NICKLAUS KRUGER ADAPTED FROM MANDRAKE’S EXPERIMENT AT <www.instructables.com> • PHOTOGRAPHS: DENVER HENDRICKS, iSTOCK PHOTOS

RE A CHING NEW F RO NTIE R S

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Sasol is not just another fuel company. It is innovative beyond belief, going right back to the company’s origins, which grew out of the wacky idea of turning coal into petrol. Sasol uses science to create magic and improve lives, and it is an established market leader in the energy industry. Renowned as an excellent employer, it also offers exceptional opportunities to talented individuals. The Sasol bursary scheme is highly sought-after and aims to attract outstanding individuals to the organisation, specifically students who are genuinely interested in mathematics and science. The goal, therefore, is to provide students with the curiosity, enthusiasm and zest necessary to appreciate science and mathematics as subjects of learning for everyone, not just scientists. If you feel you have what it takes to work for this dynamic, market-leading company, find out whether you qualify for its bursary scheme by visiting <www.sasolbursaries.com> or by calling 0860 106 235. Bursaries are on offer for full-time university studies in these disciplines: BSc Engineering, BSc and BCom. An equal-opportunity employer, Sasol awards bursaries to deserving students of all population groups.

Choose a great career in science PHYSICS Physics is the study of matter, energy, space and time, and it lies at the heart of the entire scientific enterprise. Many of the smartest people you’ve ever heard of have been physicists (think Albert Einstein and Isaac Newton), and most of what we take for granted in our daily lives – TV, satellites, microwave ovens and the like – are the result of discoveries made by these kinds of people. Physicists may work as researchers, technicians, teachers or managers in anything from acoustics to vacuum sciences – and they get to play around with all kinds of cool technology. This career is best for those who like to have fun with maths, are good at breaking down complicated systems into simpler parts, and have a desire to know what the universe is really like.

WHAT DO YOU NEED TO STUDY THIS? You’ll need to write an admission exam to study physics at a tertiary institution. For Stellenbosch University, UCT and UWC, the entry requirements for physics in 2009 are a 4 in maths and a 4 in physics; contact other institutions to make sure of their entrance rating scales. Most universities offer a three-year Bachelor of Science degree in physics (with various specialisations). You can study for a fourth year for a BSc Honours degree, which is necessary if you want to register as a natural scientist.

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s geniuses, little deeper and you’ll find award-winning scientists, math On the surface they look like your average teenagers. Dig a inventors, a young businesswoman and a national chess champion. Nothing average about the HIP2B2 Brand Ambassadors!

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Claim to fame: computer whizz and winner of Leafmap EduMotion Incentive Competition. Plans for 2008: I’m participating in the Formula One International Schools Challenge – our team recently won the SA National. I feel frustrated that I’m not doing enough to uplift the community; I can use the Brand Ambassador (BA) programme to promote science and help in that way. Contribution to the BA programme: I think I can inspire some of my school friends through my involvement, and maybe also inspire my fellow Brand Ambassadors. I’d like to raise awareness of science and technology. Favourite superhero: Shaggy, from Scooby Doo – although he’s not really a superhero, he has a lot of courage. Role model: Mark Shuttleworth. He accomplished so much, and kept his feet on the ground – most of the time. Favourite invention: the laptop computer for its mobility and power.

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Claim to fame: gold medallist in AMESA Maths Challenges. Plans for 2008: to get my learner’s licence, and to write a book, if I have the time. I plan to write my fourth-year Kathak dance exams, and I want to do very well in school – I hope to become one of the head prefects. Contribution to the BA programme: I can show people that you don’t have to be a genius to do well at and to like maths and science. Even an ordinary girl like me can do it, and I think lots of people can relate to me that way. Favourite superhero: Spider-Man – he’s a geek who saves the world! Role models: I learn different things from different people. One of my teachers has shown me how important it is always to keep the child in you alive. But my dad is the one who encourages me to do my best. It’s hip 2b square: because if you’re intelligent you have the power to be anything you want.

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Claim to fame: academic top achiever; science whizz. Plans for 2008: I hope to make the hockey A team. Academically, I hope to do well and keep getting those As. Contribution to the BA programme: I’m quite a good writer (if I do say so myself), and I think that makes me a good communicator. I’m a people person and a good team worker. Favourite superhero: Definitely Superman, because he can do everything. He has all those powers – ice breath, heat vision, strength, invulnerability. With that kind of power, he can change the world – and he does. Role model: My dad – he’s a hard worker, and he always pushes me to do my best. He also achieved a lot when he was young. Why it’s hip 2b square: maths and science are awesome and so important. They can be applied in everything we do once we leave school and will make life so much more interesting.

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BRAND AMBASSADORS

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Claim to fame: youngest person in his province to complete ICDL (International Computer Driving Licence) certificate; runs school and CT Toastmasters Club website. Plans for 2008: I want to do well academically. I also want to keep doing things better: play more sports, get involved in more school activities, improve my squash and my golf game. Contribution to the BA programme: I have some skills with computers and an aptitude for technology. Together with my ability to communicate, I think this will allow me to contribute to the programme. Favourite superhero: Batman, because he’s just a normal guy who uses his skills effectively to give himself powers and to make a big difference. I’d like to emulate that. Role model: my father – even though he’s a little older than I am (okay, a lot) he’s still very active, and he’s a good family man.

Claim to fame: national chess champion. Plans for 2008: to improve in everything, chess, academics and sport, and to maintain friendships. Contribution to the BA programme: chess has taught me analytical skills that can be very useful. I also think that travelling has taught me a lot and given me interesting experiences, and I’d like to share those benefits. Favourite superhero: Spider-Man. He has a lot of qualities and characteristics I find intriguing – responsibility, smarts – and in a fantasy world, I wouldn’t mind being bitten by a radioactive spider. Role model: Lee Iacocca. He worked for Ford, and then for Chrysler. He was determined and he never rushed, but made good choices and was always open to advice from friends. I hope to be like that someday.

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Claim to fame: Eskom Young Scientist Best Female Project winner. Goals for 2008: I’d like to invent something to combat global warming. Contribution to the BA programme: I’m very determined, and I think I can inspire others. I can help out a lot with the Adopt-A-Learner programme. Favourite superhero: Superman; he has lots of powers and he always saves the day. Role model: Nelson Mandela. He chose to forgive people who had wronged him. It’s important to move on, not to get stuck in a rut. Favourite invention: my own invention, a new method to identify a person by photographing the fundus (back of the eye). It is more reliable than fingerprints. What the world needs: innovative people to invent things so that our world continues to progress and we can live as comfortably as we can without destroying anything else in our path.

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Claim to fame: maths champion and general all-rounder. Plans for 2008: I know this sounds a bit ambitious, but I’d like to start a programme to help educate street children. I want to promote the learning of maths and make it more fun. Contribution to the BA programme: I’m very bubbly and optimistic, and when I have a plan in mind, I do everything I can to make it happen. Favourite superheroes: the Incredibles – they’ve got cool powers and they work really well as a family. Role model: Makhaya Ntini. He had a very big dream and he reached for it and achieved it. It’s important to strive for your dreams, even if you aren’t successful.

Claim to fame: young businesswoman. Plans for 2008: I want to achieve new things, to meet new people and to keep on having new experiences. Contribution to the BA programme: I think I can bring some fun and personality to it – not that I’m saying the others can’t, but I like being around people, and I like to think they like being around me. Favourite superhero: Batman, because Christian Bale played him in Batman Begins, and because he protects Gotham City and is very rich and successful. Role models: Mark Shuttleworth, Richard Branson and Michael Kors. Mark and Richard, because I look up to how much they have achieved by being such amazing entrepreneurs and still giving back to the community. And Michael Kors because in my opinion he is the most amazing fashion designer and I love his clothes.

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Claim to fame: patented two inventions (his first in Grade 5!); winner of SABS Product Design Institute, HBD Venture Capital Award. Plans for 2008: I plan to climb Mount Kilimanjaro with a friend. I also hope to get full colours for my academics, and to make the first team for rugby at school. Contribution to the BA programme: I’m very creative, I’m a team worker, and I’m pretty clever sometimes. These skills and abilities should be useful for the programme. Favourite superhero: Batman – he’s a normal human being, but he still does all this incredible stuff because he’s focused, determined and works hard. Role model: Richard Branson, because he’s very successful, he’s doing what he likes, and he’s also very innovative. I loved his book, Screw It, Let’s Do It – it was very inspirational.

SAMANT H A KH UMALO

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Claim to fame: science genius. Plans for 2008: obviously I want to get an A aggregate. I’d like to make it into the school play, and to play A-team netball and water polo. Contribution to the BA programme: I’m a good motivational speaker, and I’m good at persuading people to see things in a new way. Favourite superhero: Scooby Doo – he may not be a superhero, but he’s funny and gets stuff done in the arbest ways. Role model: Nelson Mandela. It’s so amazing how he managed to keep to his goal for so long, and achieve it without hurting other people. The world really needs more hot surfers … ha ha jokes! What the world really needs is more people who believe in themselves and strive towards their goals. Oh, and world peace …

ASH LE I GH WA TERSON

Claims to fame: hot scientist and maths fundi. Plans for 2008: I’d like to become a better public speaker. I’m auditioning for the school play, and I hope to get into that. I want to do well in sports, and obviously I’ll be working frantically on my studies. Contribution to the BA programme: my unique spirit! I believe that good things come to those who wait, great things come to those who go out and get them. I think I’m a good motivational speaker. Add my liveliness and sense of fun, and I think I can be a real asset to the programme. Favourite superhero: Spider-Man – I love the way he can climb and spin webs, and how he really tries, and he makes the right decisions even though he might have to make sacrifices. Role model: my role model is definitely Jesus Christ.

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Claim to fame: top achiever in maths. Plans for 2008: I’ve just made firstteam hockey, so I’m excited about working on that this year – being the best hockey player I can be. Contribution to the BA programme: I’m very determined and hardworking, and I think I can help inspire other people to be the same. I also think I can add a good image to the programme, because I don’t really fit into the typical ‘geek’ stereotype, even though I really am. Favourite superhero: Wonder Woman – I believe in girl power, and she’s got lots of that! Role model: I really admire Roger Federer, because he proves that you can be very, very successful and at the top of your game, if you just try hard enough. That’s a good lesson for anybody to learn. The world really needs: more Chuck Norris clones.

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WHAT DOES A BRAND AMBASSADOR DO?

Claim to fame: 90% average in science. Plans for 2008: I’m hoping to get into our school play, and to come top of my grade. I’d also like to pass my exams in ballet. Contribution to the BA programme: I’d like to do a project in the medical field (maybe to do with Alzheimer’s). I think the Brand Ambassadors can try to make HIP2B2 even more popular, along with maths and science. Surprisingly, some people think these subjects aren’t cool … Favourite superhero: Batman. He has a strong sense of justice and uses his power to do good. And Chuck Norris, because he has counted to infinity – twice. Role models: my parents – they are very inspiring. Favourite invention: fudge. What the world needs: a foolproof way to swat mosquitoes.

A HIP2B2 Brand Ambassador is the face of the HIP2B2 brand. They participate in our media channels (mag, digital and TV) to promote the HIP2B2 values and show that an interest in Science, Maths, Technology and Entrepreneurship (STEM) will reap rewards in the future. They will take subjects usually perceived as boring or “square” and add their own unique spin to them – using the HIP2B2 media.

creating a weekly blog for the site; will do a year-long project which might then be presented to Mark Shuttleworth; they will also each be involved in a community outreach initiative. They will select which media areas they would like to focus on, either television or editorial (magazine or website). They have been given several diverse options to choose from: writing event reviews, being a reporter ‘in-thefield’, reviewing books, creating video and podcasts, and so on.

HOW WERE THEY CHOSEN?

We advertised in our magazine and our website <www.hip2b2.com>. Applicants completed an application form, as well as a motivating letter from a parent or teacher. After shortlisting, we conducted telephonic interviews, and each candidate was asked to submit a task related to their chosen category. Academic results were not the only determining factor – we wanted young people who are passionate about their areas of interest. WHAT WILL THEY DO?

They will be actively involved in the media channels, and have already learnt valuable media skills during the orientation weekend: they now know how to edit video and create podcasts, and have the software to do so. They will commit to

COULD I STILL BECOME A BRAND AMBASSADOR?

At the moment, we are not taking on any additional Brand Ambassadors. Having said that, if you really feel that you have brains, confidence, a great personality, a passion for either science, maths, invention, entrepreneurship or computers, and a strong desire to inspire and share this passion with other learners – you may email <ambassador@hip2b2.com>. We will then send you the application form and instructions. Who knows, perhaps you could be made an honorary Brand Ambassador?

INTERVIEWS: NICKLAUS KRUGER ∙ PHOTOGRAPHS: DENVER HENDRICKS ∙ HAIR & MAKE-UP: MARELI SERFONTEIN, MELANIE RIGBY, <www.mobilemakeup.co.za>

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Kate Evans, Communications Manager of BSquare Communications, gives us the low-down on the Brand Ambassador (BA) programme.

Check out the blogs for each of the Brand Ambassadors under the HIP2B2 section at <www.hip2b2.com>.

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Balancing the scales: equations They’re everywhere: in science, biology and in your maths textbook. Tip the scale of power in your favour by learning how to solve equations. In the language of algebra, an equation – a mathematical expression containing an equals sign – is a basic number ‘sentence’. Note the words equals and equation. Try to think of an equation like a balance scale. At any one point, the mass on both sides should be the same. The general rule is that whatever you do on the one side, you must also do on the other side to prevent the scale being unbalanced.

CAN EQUATIONS BE RATIONAL?

• A rational equation is an equation in which at least one denominator contains a variable (a fraction with the bottom part containing x). • When a denominator contains a variable, there is a restriction on the domain. The variable cannot take on any number that would cause any denominator to be zero. (You cannot divide a fraction by zero.) • The first step in solving a rational equation is to convert the equation FOR EXAMPLE to an equivalent equation without on one denominators. Get all the xs umbers n 10x + 4 = 5x – 3 side and the her • The next step is to set the equation on the ot equal to zero and solve. 10x – 5x + 4 = 5x – 5x – 3 th • Remember that you are trying to bo om fr x 5 Subtract equation isolate the variable. sides of the 5x + 4 – 4 = –3 – 4 om Subtract 4 fr THE ROOT OF THE PROBLEM 5x = –7 both sides Divide both When we look at equations involving square x=– sides by 5 root signs, it is important to isolate the square root on one side and then square both the left- and the right-hand sides. Make sure to check your solutions by substituting them back into the original equation.

QUADRATIC EQUATIONS

A quadratic equation is a polynomial equation of degree 2. A quadratic equation has two solutions: either two distinct real solutions, one double real solution or two imaginary solutions. The U-shaped graph of a quadratic is called a parabola. There are a few methods you can use to solve a quadratic equation: • factoring; • completing the square; and • quadratic formula. All methods start with setting the equation equal to zero.

BY LIVING MATHS ∙ PHOTOGRAPH: iSTOCK PHOTOS

A SCALE OF BALANCE

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37 QUESTION 1

QUESTION 2

2(3x – 7) + 4(3x + 2) = 6(5x + 9) + 3 6x – 14 + 12x + 8 = 30x + 54 + 3 18x – 6 = 30x + 57 –6 = 12x + 57 –63 = 12x x=– =– x =–

5x – 6 = 3x – 8 2x – 6 = –8 2x = –2 x = –1 Tip Check the solution by substituting –1 in the original equation for x. If the left side of the equation equals the right side of the equation after the substitution, you have found the correct answer. Left side: 5(–1) – 6 = –11 Right side: 3(–1) – 8 = –11 SOLUTIONS

Tip Check the solution by substituting in the original equation for x. If the left side of the equation equals the right side of the equation after the substitution, you have found the correct answer. Since the left side of the original equation equals the right side of the original equation when the value – is substituted for x, the solution x = – is verified.

Solve for x in the following equations. 1. 5x – 6 = 3x – 8 2. 2(3x – 7) + 4(3x + 2) = 6(5x + 9) + 3 3. x + 1 – 3x = 1 WORK IT OUT

QUESTION 3

x + 1 – 3x = 1 Tip The square of any positive number is positive and the square of 0 is 0. Therefore, negative numbers cannot have a real square root. x + 1 = 3x + 1 ( x + 1)2 = (3x + 1)2

n the equatio oth sides of Add 3x to b is isolated radical term so that the sides Square both

x + 1 = 9x2 + 6x + 1 0 = 9x2 + 5x 0 = x(9x + 5) x = 0 or

EINSTEIN’S EQUATION

Check the solution by substituting 0 and – individually in the original equation for x. If the left side of the equation equals the right side of the equation after the substitution, you have found the correct answer. x = 0 is the correct answer.

Albert Einstein is the father of one of the most recognisable equations: E = mc2 According to Einstein’s theory, as an electron approaches the speed of light, the kinetic energy is converted into mass, making the electron much heavier. This means that the electron requires an infinite amount of energy to reach the speed of light, but by this time it will already have an infinite amount of mass. Why is this a problem? Could we simply give the electron an infinite amount of energy? We would if we could but this universe does not have infinite amounts of energy, so we cannot make an electron (or anything else) travel as fast or faster than the speed of light.

SMART MATHS


Test matches and one-day games are more scientific than just smashing the ball heavenwards.

THE HELMET The outside of a cricket helmet is rounded to deflect the ball as much as possible, with a front brim to protect the eyes. The grill protects the main part of the face. Made of simple steel or hardcore titanium, it must be strong enough to stop a very fast-moving ball. Titanium (symbol Ti) is 40% lighter than steel and far more durable. It has a tensile strength of 241–552 MPa: it can withstand 2 461–5 624 kg/cm2 before it breaks (depending on the grade). This gives titanium the highest strength-toweight ratio of any metal today.

BALL GUARDS Ball boxes, made of hardened moulded plastic with foam lining for impact protection, are traditionally triangular and convex. New styles are elongated to fit the shape of the pubic area. The ergonomic design allows for maximum protection of vulnerable parts without hindering the batsman’s run. Abdominal guards for women are flatter and cover more of the pelvic area. Some women also use chest pads.

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BY JACQUI LUND • PHOTOGRAPHS: GALLO/GETTYIMAGES.COM, iSTOCK PHOTOS

Get into gear

THE WILLOW Cricket bats are traditionally made from a willow tree called Salix alba cearulea. A top quality cricket bat contains 12% moisture. Batsmen oil their bats with linseed oil, which is easily absorbed into the cells of the wood. Its slow drying time allows for maximum absorption into dense wood. This seals in the moisture and softens the bat to prevent cracking. It also waterproofs the willow. Most important in choice of bat are balance and pick-up. Pick-up is the centre of gravity in the bat. The ‘sweet spot’ of the bat is the heaviest point in the bat. The average weight of an international cricketer’s bat is 1,13 kg, but there is no minimum or maximum weight. A lighter bat allows faster bat speed and increases the chances of middling the ball. A heavier bat may hit the ball harder, but it will be more difficult to find the sweet spot.

THE PADS Pads protect the front and sides of the leg, and must be as streamlined and light as possible. The exterior is usually made from high quality polyurethane; inside, core rods of foam and cane provide stability and flexibility. Polyurethane (PU) is a polymer consisting of a chain of organic units joined by urethane links. Polyurethane polymers are formed by a reaction between a monomer containing at least two isocyanate functional groups and another monomer containing at least two alcohol groups in the presence of a catalyst. If you feel inspired to take your sport to a new level, why not try your hand at a game of Space Quidditch? Visit <www.hip2b2.com> for more exciting ways to keep fit in the year 2020.

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The playing field

SPORT SCIENCE

WORK IT OUT

If a cricket ball is bowled at 100 km/h and the batsman swings the bat at 60 km/h, how fast does the ball come off the bat? This depends at what point ball meets bat and how fast the ball would ricochet if the bat simply blocked it. Suppose that the bat blocks the ball and the ball bounces off the bat at 20 km/h. If E = ratio of bounce speed to incident speed (usually 0,1–0,3), and V = bat swing speed, the equation to work out ball speed off the bat will be: 20 + (1 + E)V = 20 + 1,2 x 60 = 20 + 72 = 92 km/h.

ATION REPAR P H C PIT nce. Pitch t and a scie ar but an is is Th -round job, ce is a year nsively an n te te in n ai ts m match star a r fo n io re a game. preparat n days befo ve se to ve ich pitch to about fi chooses wh an sm d the n u The gro ailable on options av e th ss f ra o g t e u use o ims th he evenly tr t, re ex o N m e. y el ar squ gressiv it daily, pro er s ft er A at . w es d h an proac up e match ap th ed ll as ro y tl e, h in g h li lling mac ro e th to es ay ad that com five hours for four to mpressed. co y tl and down ec soil is corr e th arked re su e make lines ar m the game, f o n with ay w d ra e d On th ine and tw d an es ak 2 yards out with st measures 2 ch it p e Th . e popping whitewash (3,66 m). Th et fe 2 1 y b 1,22 m in (20,1 m) ne is drawn li e se ea cr ) end, with th (batting ps at each m u st e . th se f front o owling crea along the b stumps set

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PERFECT PITCH The condition of the pitch has a big impact on the game. Russell Adams, team manager of the Cape Cobras, gives us the basics: • Atmospheric conditions: if it’s cloudy, the ball swings more. If it’s dry and hot, it swings less. • Grass: if there is very little grass on the pitch, it’s likely to be a good batting pitch. More grass means the ball grips better, so favours movement of the ball, which is better for seam bowlers. • Moisture: a dry pitch bounces more, a wet pitch less. Bulli soil is used on cricket pitches for its strong swell/shrink characteristics. It is very absorbent, becoming dark when wet. As it dries out it gets much lighter. Cricketers and groundsmen judge the dryness of a pitch by how light or dark it is.

A STICKY WICKET A poorly prepared wicket can ruin a game by making runs too easy to come by, or allowing bowlers to dominate. In 2005 South Africa was involved in a high scoring draw in the West Indies. The Proteas came in to bat in their first innings and made 588 for 6 declared on a pitch regarded as a featherbed (the term given to wickets that are generally easy to score on). The West Indies replied with a massive total of 747, allowing South Africa the chance to bat again only on day five. However, the record for boring batting cricket goes to a match between Sri Lanka and India in 1997. India, batting first, amassed 537 for 8 declared. Sri Lanka then batted the Indians into oblivion for four days, scoring a ridiculous 952 for 6 declared.

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CRICKET

WHO TO LOOK OUT FOR IN 2008 FAST FACT

Overarm bowling was invented by Christine Willis in 1805 to overcome the problem of hooped skirts blocking delivery.

MITCHELL JOHNSON: Australia, leftarm fast bowler. He’s taken 40 wickets in just 25 one-day internationals and recently made his test debut against Sri Lanka, taking four wickets in a test that Australia won easily. Australian bowling legend Dennis Lillee has labelled Johnson a ‘once in a generation bowler’ because of his excellent abilities with the ball in hand.

ALBIE MORKEL: South Africa, hard-hitting all-rounder. Morkel marked his intent for the season with a dynamic batting display in the Twenty20 World Cup and a nerveless bowling performance in the series win against Pakistan last year.

LADIES ON THE PITCH The first official recorded women’s match was a county match in England in 1811. It was Surrey versus Hampshire, played at Ball’s Pond, London. The first women’s World Cup Cricket tournament took place in England in 1973. Interestingly, it was also the first Cricket World Cup ever. The men only got their own World Cup in 1975. Two stars of the South African women’s team are Olivia Andersen and Johmari Logtenberg. Johmari was the youngest cricketer ever to play for the national side. She played her first game for South Africa against England at the age of 14, scoring a fantastic 74 runs. Olivia, 19, made her South African women’s cricket international debut against Pakistan in November 2007. ‘I started in the boy’s cricket team at school and went on to play men’s club cricket. It was tough at first, because I was often ridiculed by the boys on the team,’ she says. The bullying almost forced her give to up. But she hammered their ‘useless girl’ perceptions on the head, and now represents her country. WOMEN’S TEST MATCH

MEN’S TEST MATCH

Duration

Four days

Five days

Ball weight

142 g

156 g

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ROBIN UTHAPPA: India, explosive right-hand batsman. After scoring over 800 runs in just seven domestic games in India, the selectors introduced hard-hitting Uthappa into the national side. He’s made a modest start to his international career, but some big hits in the Twenty20 World Cup have signalled the start of fireworks. Local rising star LONWABO LOPSY TSOTSOBE: Warriors, left-arm fast-medium bowler. Impressive Supersport Series figures, plus six wickets against the touring New Zealanders for SA ‘A’ last year have given Tsotsobe a huge boost. And again, having a nippy left-hander is a boon* for any bowling attack. *boon (noun): a thing that is helpful or beneficial; blessing.

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INTELLIGENT ENTERTAINMENT

BY MICHELLE VILJOEN • PHOTOGRAPHS: GALLO/GETTYIMAGES.COM

PRESS

PLAY

THE DAYS World Wetlands Day is on 2 February. Be kind to our fishy friends by not littering in our wetlands and rivers. • Don’t shy away from spreading some luuurve on Valentine’s Day, 14 February, but do it smartly. THE FESTIVALS See the locals strut their art stuff at the Suidoosterfees, featuring local music, dance, theatre and more, at Artscape, Cape Town, from 1 to 3 February. Visit <www.suidoosterfees.co.za> for more. • Stop holding your breath! After two years, the Up the Creek Festival is back. Camp out near Swellendam with hot local talents like Van Coke Kartel, Taxi Violence and The Parlotones from 1 to 3 February. Visit <www.upthecreekfestival.co.za> for more. THE EVENTS Look down a hungry lion’s mouth. Okay, not really, but you can come close to your favourite wild animals: help to keep the Johannesburg Zoo clean and the animals happy by volunteering for its Community Service Project. For details, visit <www.jhbzoo.org.za> or call 011 646 2000. • Get an inside peek at what goes on at the South African Astronomical Observatory in Cape Town at an open night on 9 February. You’ll get a tour, check out the astronomers’ gear of yesteryear and look through a telescope. Visit <www.saao.ac.za> or call 021 447 0025. • Adrenaline junkies, listen up! The thrilling Thrombi X-fest in Thrombosis Gorge in Underberg, KZN, from 15 to 17 February features extreme kayaking, speed climbing, downhill mountainbiking, paragliding … you get the picture. Glide through <www.xfest.co.za>. THE GAME It’s time to pull your racing gloves closer and get into some serious horsepower. Yes, it’s here – the Ferrari Challenge for PS3. It’s the officially licensed racing simulation that features the entire highpowered Ferrari production line since 1947. Get your crash helmets on. THE MOVIES Jane (Katherine Heigl) is a professional bridesmaid. Well, after 27 trips up the aisle, but always in the bride’s footsteps, she could be. In 27 Dresses she is asked to be her sister’s bridesmaid, but Jane is secretly in love with the groom. What is a bridesmaid to do? Check it out on 1 February. • We’ve been there, done that and seen the movie in which a ragtag bunch of football/ baseball/hockey players is transformed into an all-star team by an over-the-hill coach. And now a spoof of these inspirational sports movies has hit the circuit. The Comebacks opens on 8 February.

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1/7/08 10:16:07 AM


Jacques talks about his new album, life after Idols and the SA music scene

Being in the top three of Idols in 2003 changed my life in a big way. After Idols it was hard work to sustain a name and a public profile. In the past three-and-a-half years I’ve dedicated myself to my new album, The Colour Red. It’s completely different to my first one. It has a funky R&B flavour. My first CD was a contemporary jazz album. I was studying music at UCT at the time, which probably influenced my style. It was quite daring to go the jazz route because the record company, maybe, expected something a bit more pop oriented and commercial, but I decided to stay true to myself. When I was studying music at UCT, Zolani, the lead singer of Freshlyground, was my neighbour. She used to come over and we’d share ideas – I’d sing and she’d play the guitar. Then suddenly, Freshlyground was huge! It’s wonderful to watch that happen. The best thing about making an album is having the creative freedom to explore. Hearing a melody evolve from its rawest state into the final product is so enjoyable. It’s a great journey and you only realise how great when you’re writing your thank yous for the inside sleeve [of the CD].

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My most memorable day on this project was when I found out Akon had agreed to sing on one of my songs. I never actually met him, but he had to approve my voice and I sent him the melody I’d written. I’m blessed to have collaborated with a big international name. The invention that’s changed my life is a CD frontloader, because it allows me to listen to all kinds of music while I’m driving, and I love driving. I think the smartest person alive is Mr Mandela. You have to be pretty smart to achieve what he has. Smartness, to me, is wisdom; having a humble attitude is smarter than anything else. Richard Branson also stands out – he is an amazing entrepreneur. MY FAVOURITE SA BANDS

Prime Circle – they write good songs and have an international flavour. Watershed, Cassette and The Parlotones are really cool. Pebbles, nominated in 2007 for a SAMA, features on my single ‘I Won’t Forget’. Her voice has a jazzy feel, which combines well with the dance tempo of the song.

COMPILED BY: NIKKI BENATAR • PHOTOGRAPHS: UNIVERSAL

OPINION: MUSIC

1/7/08 4:01:37 PM


THE FRESHEST JAMS OF 2007

If you feel like you missed out on last year’s hottest albums, you might want to update your CD collection with our guide to 2007’s musthave music. Best pop • Kylie Minogue X • Maroon 5 It Won’t Be Soon Before Long • Feist The Reminder • James Blunt All the Lost Souls • Plain White T’s Every Second Counts • Freshlyground Ma’Cheri • Britney Spears Blackout • Michael Buble Call Me Irresponsible

Best rock and alternative • Radiohead In Rainbows • Linkin Park Minutes to Midnight • Interpol Our Love to Admire • The Arctic Monkeys Favourite Worst Nightmare • The Killers Sawdust • The Parlotones A World Next Door to Mine • The Dirty Skirts On a Stellar Bender • The Springbok Nude Girls Peace Breaker • Led Zeppelin Mothership • Modest Mouse We Were Dead Before the Ship Even Sank • The Shins Wincing the Night Away • Foo Fighters Echoes Silence Patience & Grace • The Hives Black and White Album

Best R&B and soul • Rihanna Good Girl Turned Bad • Alicia Keys As I Am • Craig David Trust Me Best hip-hop and rap • 50 Cent Curtis • Kanye West Graduation • Jay-Z American Gangster Best kwaito • Kabelo I’m a King • Stoan Seate Heart of Stoan • L’Vovo The Teddy Bear • HHP Acceptance Speech

GIVEAWAYS Explore the inner workings of the human body in Alive – The Ultimate Pop-Up Human Body Book (it even includes the sound of a heartbeat!). Or delve into your family lineage with the Family History Kit, complete with an interactive album, a family tree poster and a CD-rom. GIVEAWAY NAME: Alive GIVEAWAY NAME: Family

Amabokke fever might have died down a bit since the Rugby World Cup, but you can keep the game going. We have one Rugby 08 PS 2 game to give away. GIVEAWAY NAME: Rugby

TO ENTER

Write to: HIP2B2 Giveaway, PO Box 440, Green Point 8051 or email <win@hip2b2.com>. Please include the name of the giveaway, your name, contact details, school and grade. You can also SMS HIPCOM followed by the giveaway name to 35978. Each SMS costs R3. The closing date is 28 February 2008. Winners will be notified directly.

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1/9/08 9:10:33 AM


THE FRESHEST JAMS OF 2007

If you feel like you missed out on last year’s hottest albums, you might want to update your CD collection with our guide to 2007’s musthave music. Best pop • Kylie Minogue X • Maroon 5 It Won’t Be Soon Before Long • Feist The Reminder • James Blunt All the Lost Souls • Plain White T’s Every Second Counts • Freshlyground Ma’Cheri • Britney Spears Blackout • Michael Buble Call Me Irresponsible

Best rock and alternative • Radiohead In Rainbows • Linkin Park Minutes to Midnight • Interpol Our Love to Admire • The Arctic Monkeys Favourite Worst Nightmare • The Killers Sawdust • The Parlotones A World Next Door to Mine • The Dirty Skirts On a Stellar Bender • The Springbok Nude Girls Peace Breaker • Led Zeppelin Mothership • Modest Mouse We Were Dead Before the Ship Even Sank • The Shins Wincing the Night Away • Foo Fighters Echoes Silence Patience & Grace • The Hives Black and White Album

Best R&B and soul • Rihanna Good Girl Turned Bad • Alicia Keys As I Am • Craig David Trust Me Best hip-hop and rap • 50 Cent Curtis • Kanye West Graduation • Jay-Z American Gangster Best kwaito • Kabelo I’m a King • Stoan Seate Heart of Stoan • L’Vovo The Teddy Bear • HHP Acceptance Speech

GIVEAWAYS Explore the inner workings of the human body in Alive – The Ultimate Pop-Up Human Body Book (it even includes the sound of heartbeat!). Or delve into your family lineage with the Family History Kit, complete with an interactive album, a family tree poster and a CD-rom. GIVEAWAY NAME: Alive GIVEAWAY NAME: Family

Amabokke fever might have died down a bit since the Rugby World Cup, but you can keep the game going. We have one Rugby 08 PS 2 game to give away. GIVEAWAY NAME: Rugby

TO ENTER

Write to: Hip2b2 Giveaway, PO Box 440, Green Point 8051 or email <win@hip2b2.com>. Please include the name of the giveaway, your name, contact details, school and grade. You can also SMS HIPCOM followed by the giveaway name to 35978. Each SMS costs R3. The closing date is 28 February 2008. Winners will be notified directly.

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1/7/08 4:03:05 PM


.,

OPINION: MOVIES

3-D … getting deep into the movies. This picture and right: Ray Winstone and Angelina Jolie feature in Beowulf, which pioneers Real D, the latest hyper-realistic 3-D technology.

Want to feel that you’re not just at the movies but practically in them? Three-D is the process by which filmmakers create the illusion of depth in the moving, cinematic image. The idea is that by making the image three-dimensional, it will ‘jump’ from the screen into the real world, allowing the viewer to feel part of the movie. The technique of shooting films in 3-D, known as stereoscopy, involves filming two images simultaneously, on two identical cameras, side by side. The idea is to capture an identical image for each eye. So when you see two separate but identical images of an object your brain perceives it as a single three-dimensional object. FAST FACT

The first 3-D film ever shown was The Power of Love, which was screened in 1922.

MOVIES THROUGH NEW EYES

Until recently, watching a movie in 3-D meant you had to wear a pair of rather silly-looking cardboard glasses with one red and one green lens. The reason for this was that when 3-D films were screened, two separate images were projected onto the cinema screen simultaneously. Filmmakers tinted one image red and one green, so when you wore the glasses, the red lens allowed that eye to see only the red image and the green lens blocked out everything except the green image. This was to trick our brains into seeing one threedimensional image.

POPULAR 3-D

The popularity of making movies in 3-D waned because it was so much more labour intensive than making normal films. You had to have two identical cameras, two very expensive film reels, as well as two projectors with projectionists, before you even got to the special silver screens any movie theatre would need specially fitted. Three-D movies became popular again in the 1980s once technology advanced enough that instead of requiring two of everything, filmmakers could put the entire movie onto a single film reel.

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1/7/08 10:16:53 AM


BY EESHAAM SEPTEMBER AND NICKLAUS KRUGER • PHOTOGRAPHS: iSTOCK PHOTOS, © 2007 WARNER BROS AND INPRA

NEW LIFE FOR 3-D

Now the latest technology has allowed 3-D movies to stage a comeback. With new digital cameras and the 3-D-imaging software perfected in modern video games, filmmakers can produce more believable 3-D effects. Think of Spy Kids 3-D: Game Over and The Adventures of Sharkboy and Lavagirl in 3-D, where 3-D footage is integrated with 2-D footage. Recently on the big screen in this advanced 3-D format were Meet The Robinsons, The Nightmare Before Christmas and the new fantasy epic, Beowulf. These films are all pioneering a new digital format for the production of 3-D footage, called Real D. Here, a single digital projector coupled with a powerful computer server alternately displays clockwise and counterclockwise polarised images at 144 frames per second – much higher than the frame rate for standard 2-D films, which is 24 frames per second.

BEYOND THE THIRD DIMENSION When we talk about watching movies in 3-D, we actually mean we’re watching it in 4-D. Why? According to Albert Einstein (and another clever guy called Henri Poincare), we live in a four-dimensional universe, not a three-dimensional one – the extra dimension is the time dimension. Physics requires us to treat time as another dimension. Think about it this way: if you have to arrange to meet somebody, you need to give them information in four dimensions. For example, you might tell them to meet you in

Real

the building on the corner of Second Avenue and Short Street, on the third floor (that takes care of your three spatial dimensions) at 10 am (your time dimension). Some physicists think there may be many more dimensions, curled up too small for us to see, or curved in ways that prevent us perceiving them. String theorists – who think the universe is made up of little subatomic vibrating strings, and who use very impressive maths – think there are 10 or 11 dimensions, or even more. To learn more about this, search for ‘string theory’ on <www.youtube.com>.

D vs

2-D

• Images displayed: 144 frames/second

• Images displayed: 24 frames/second

• Smoother effect

• Jumpy effect

• Glasses with grey lenses (different polarisation)

• No glasses required

Two-D and 3-D footage are combined in The Adventures of Sharkboy and Lavagirl in 3-D. TRY THIS AT HOME!

BY EESHAAM SEPTEMBER

Experiment: explore the ‘depth’ of the third dimension at home. Stand just a little bit less than your arm’s length from a door, now reach out and grab the door knob. Shockingly easy, right, but not pointless: now close one eye, reach out and grab the door knob again. It is more than likely that you missed by just a little bit. That is because we need both eyes in order to see in three dimensions; without two identical images of any object collected by our eyes, we have no depth perception.

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1/7/08 10:17:32 AM


OPINION: BOOKS

Writing from South Africa, edited by Anthony Adams and Ken Durham, reviewed by you. SAMANTHA MAKHOSAZANA KHUMALO

ASHLEIGH WATERSON

Grade 11, Northcliff High School, Johannesburg

My overall impression of the book was it is educational but fascinating as well. I learnt a lot about Apartheid through the humorous stories. The main message of the book is Apartheid was a very unjust racial policy that caused major destruction in our country through pettiness about trivial things like the colour of a person’s skin. My favourite short story was Unto Dust because the story has an ironic ending. These stories are still relevant today because we can learn from it so we don’t repeat our mistakes. I think a good alternative title for this book would be ‘Through the Eyes of our People.’ My least favourite story in the book was Why? Fanyang because I was lost at times and couldn’t relate to the characters at all. I did not think there should be less focus on Apartheid in these stories, but there could have been a few stories from before or after Apartheid to contrast the different societies and changes. I thought the use of photographs were brilliant and very representative. If I were asked to add a story to this book about an experience, I would add a story about how society has changed since Apartheid. I would contrast the lives of young people born after 1994 to their parents who lived through Apartheid. I would call it ‘Amalgamation’.

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Edited by Anthony Adams and Ken Durham, Writing from South Africa is a collection of short stories exploring South Africa in the twentieth century. With stories by everyone from Herman Charles Bosman, Normavenda Mathiane to D. Can Themba, this book takes a hard, witty and sometimes even funny look at Apartheid, racism and political tension, and what it means to be South African.

I really found the book very interesting and I enjoyed it. The main message of the book is to show South Africa’s progression over the years. My favourite short story was Labour Pains. I liked it because it showed how people can unite to help each other. I think these stories are still relevant today because they show South Africa’s past, and our past makes us who we are. I think a good alternative title for this book would be ‘Stories from South Africa’s Past.’ My least favourite story in the book was Unto Dust. I did not like the racial terms, but the ending made up for it. I don’t think there should be less focus on Apartheid in these stories. It is what made South Africa what it is today. It’s important that we see and understand South Africa’s past. I really enjoyed the use of photographs in this book. I think that they are a clear representation of the stories within the book and they are beautiful. If I were asked to add a story to this book about a personal experience, my story would also be about Apartheid because it hasn’t completely gone away. I’d base it on a friend’s experience where racism was an issue.

COMPILED BY NICKLAUS KRUGER • PHOTOGRAPHS: DENVER HENDRICKS

Grade 11, Redhill High School, Johannesburg

Would you like to review a book for us? Write to: HIP2B2 book reviews, PO Box 440, Green Point 8051 or email: <talk2us@hip2b2.com>. Please include your name, contact details, address, school and grade.

1/9/08 11:07:07 AM


THINK TANK

BRAIN BUSTERS ADD IT UP

PRIME TIME

The small, black numbers are sum totals of the sum boxes beneath or to the right of the sum totals. Using only the numbers 1 to 9, complete the sum boxes so that each one is composed of unique numbers only – in other words, in each sum box, the same number cannot be used more than once. For example: a sum total of 6, over a sum box of three blocks can only have the solution 1 + 2 + 3 (in any order). 22 24

30

11

45

8 9

6

1 7

42

6

15

1 2

11

4

9

8

11

8

1

13

4

What is the sum of all the prime numbers between 80 and 100? BUILD A WORD

Make 10 words out of the following 20 words by matching them up correctly. For example: WATER + SHED = WATERSHED. Some words have more than one possible match. You must end up with the 10 correct words, not phrases. house

butter

boy

tea

bone

fly

cloth

cake

table

sauce

mountain

meal

side

bottle

cup

bell

light

cheese

blue

pan

9

13

14

12

6

5

42

7

4

11

5

1

9

4

3

8

8

9

24

30

22

13

8

9 4 13 8

3 1 7 11

8 6 4 7 5 2

6 9

1 3 45

2 8 11

9 2 11

3 1 4

3 7

PRIME TIME 83 + 89 + 97 = 269

16

3 1 4 2

WHAT’S NEXT? 57 and 93. Starting with 2, systematically add the square numbers 1 (12); 4 (22); 9 (32); 16 (42); 25 (52); and so on, to get the sequence.

5 15

REARRANGE IT

TREASON.

BY ELLEN CAMERON • ILLUSTRATIONS BY ANTON PIETERSEN

4

6

__

21 11

__

4

32

7

16

1

7

5

3

3

2

7

What are the next two numbers in the sequence?

35

WHAT’S NEXT?

34

Using the letters in the word SENATOR, make another seven-letter word that refers to the crime of betraying one’s country or government.

Did you get 360? The only prime numbers between 80 and 100 are 83, 89 and 97. 91 is divisible by 7 and 13 and is therefore not a prime number.

REARRANGE IT

6

6

1

2

5

9

7

34

ANSWERS

5

35

16

8

3

7

21 11

8

11

4

2

14

BUILD A WORD Butterfly, saucepan, teacup, lighthouse, bluebottle, bonemeal, bellboy, tablecloth, mountainside, cheesecake.

12

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1/8/08 8:21:32 AM


SIMPLY SCIENCE

YOU USE A REMOTE CONTROL? PRESSING BUTTONS

Infrared radiation

Every time you channel-hop, your remote control transmits coded messages via invisible light waves to receivers on certain devices. When you press a button on the remote control, this completes a circuit on the circuit board inside. This sends the appropriate command (in binary) to the LED* at the front of the remote. From there, the message is then transmitted via light waves to the receiver on the device concerned. And just like that, the volume/brightness/channel/etcetera on your television changes to whatever you desire.

Most home remote controls use infrared radiation (IR), a form of light that’s just ‘below’ visible light on the electromagnetic spectrum. IR remotes have a range of only about 10 metres, and can’t work through walls or around corners. Some everyday sources of infrared interference are sunlight, fluorescent bulbs and the human body. Car-alarm remote controls, garage door openers and several other remote controls use radio waves instead, which are effective up to a distance of 30 metres and can travel through walls.

*Light Emitting Diode This is a two-terminal component allowing an electric current to flow in one direction.

How it works

The message sent includes: • a start command; • the command code for the operation concerned (such as volume up); • the device address (so the device knows the command is meant for it); and • a stop command (triggered when the button is released).

Circuit board

LED

Signal

Receiver

BY NICKLAUS KRUGER • PHOTOGRAPH: iSTOCK PHOTOS

DID YOU KNOW?

Different devices and electronic brands use different codes for their commands. That’s why you can’t work your Sony television with your Samsung radio remote control. Universal remote controls are designed to work with a range of devices that all use the same commands – but they must still be of the same brand.

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1/7/08 10:21:08 AM


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