AQA GCSE (9-1) Physics Teacher Pack Look Inside by Collins

Chapter 1: Energy

Energy: Introduction When and how to use these pages This unit, as the name implies, is all about energy. Nothing in the Universe can happen without a transfer of energy; gaining an understanding of energy will lead to an enhanced understanding of the Universe, how things work, why things are as they are and indeed life as we know it. This unit ingrains the idea that energy can be determined by measurements and that an appreciation of energy can help us make informed decisions about our uses of energy and their consequences. These pages are designed either for following fully or for dipping into for ideas and inspiration, including practical work, or somewhere in between.

Overview of the unit

Potential energy

Consider what happens when a spring is stretched. Describe what is meant by gravitational potential energy.

Describe how the kinetic energy store of an object changes as its speed changes.

Investigating kinetic energy

Calculate kinetic energy. Consider how energy is transferred. Understand what is meant by work done.

Work done and energy transfer

Explain the relationship between work done and force applied. Identify the transfers between energy stores when work is done against friction.

Define power.

Understanding power

Compare the rate of energy transfer by various machines and electrical appliances. Calculate power.

Understand how things heat up.

Specific heat capacity

Find out about heating water. Find out more about specific heat capacity.

Required Practical: Investigating specific heat capacity

Use theories to develop a hypothesis.

Dissipation of energy

Explain ways of reducing unwanted energy transfer.

Evaluate a method and suggest improvements. Perform calculations to support conclusions.

Describe what affects the rate of cooling of a building. Understand that energy is dissipated.

Obstacles to learning

Overarching objectives

Calculate the energy stored by an object raised above ground level.

In this unit, pupils will learn about the many different types of energy. They will look at transfers between different types of energy, especially elastic potential energy, gravitational potential energy and kinetic energy. Pupils will look at work done and power and how they are useful in different ways. Various units will be introduced, including the joule and the watt. Pupils will also look at temperature and how this relates to energy. Within this context, they will recognise that different substances have different specific heat capacities and the consequences of this, e.g. causing the wind between the land and the sea. Pupils will use the law of conservation of energy and will look at both useful and waste energies. They will learn about efficiency; not just how to calculate it but also the importance of improving the efficiency of transducers and various ways in which this can be done. Pupils will look at the different energy resources of Earth that are used, particularly in terms of generating electricity. They will explore the advantages and disadvantages of the different resources and how our use of such resources may change in the future, both at a local and a global scale. Pupils will begin to be able to make informed decisions about their own energy use in the future. Within this topic, there are two core practicals, alongside many others, that provide opportunities for pupils to become more familiar with the scientific process, including developing and testing a hypothesis and processing, analysing and evaluating results to reach suitable conclusions.

Lesson title

Energy efficiency

Explain what is meant by energy efficiency.

Required Practical: Investigating ways of reducing the unwanted energy transfers in a system

Use scientific ideas to make predictions.

Calculate the efficiency of energy transfers. Find out about conservation of energy.

Pupils may need extra guidance with the following terms and concepts:

• Energy itself is a tricky concept. It is often used incorrectly in everyday speech – “I have no energy today”; the use of models and experiment can be very useful in helping with this, especially in terms of being able to understand what is actually happening.

Evaluate an experimental procedure. 10

Describe the main energy sources available for use on Earth.

Using energy resources

Distinguish between renewable and non-renewable sources.

• Some of the numbers with energy can be very large or very small. Not only are these numbers difficult to

understand, they can be tricky to use in calculations. It is easier to try the calculations first with easier numbers and then with trickier numbers. Indeed, this can be a good tip even when easier numbers are not provided. Sometimes pupils find it easier to make up easy numbers where they can easily see what to do and then apply the same logic with the more difficult numbers.

Explain the ways in which the energy resources are used. 11

Global energy supplies

Analyse global trends in energy use.

Key concept: Energy transfer

Recognise objects with energy.

Understand what the issues are when using energy resources. Recognise the different types of energy.

• Temperature and thermal (heat) energy are often confused by pupils. It may be useful to establish clearly that temperature is not an energy, although it is related to the average kinetic energy of the particles, whereas thermal (or heat) energy is the energy that is transferred when temperature changes.

Describe energy transfers. Use and describe the law of conservation of energy. 13

Substitute numerical values into equations and use appropriate units.

Maths skills: Calculations using significant figures

• The idea that certain energy resources can lead to global warming and its implications can be alarming for

Change the subject of an equation.

some pupils. They need to understand that we are not past a tipping point and that we can all make positive changes for the better.

• The whole debate on energy resources is one that people can have strikingly polar views on so needs to be

Analyse data to identify trends.

Give an answer using an appropriate number of significant figures. 14

Recognise the difference between mean, mode and median.

Maths skills: Handling data

Explain the use of tables and frequency tables.

presented and coordinated to ensure that all views on this can be challenged but respected.

Explain when to use scatter diagrams, bar charts and histograms.

Practicals in this unit In this unit, pupils will do the following practical work:

• Required practical: determine the specific heat capacity of different substances • Required practical: investigate cooling curves for different thicknesses of material AQA GCSE Physics: Teacher Pack

AQA GCSE Physics: Teacher Pack

Chapter 2: Electricity

Lesson 1: Static electricity

Explain

Jigsaw: The students split into five groups; each group should be given a situation involving static electricity and access to research materials. Students should use the research materials to find out about their given situation. Students should be given a situation appropriate to their level:

Lesson overview AQA Specification reference

• Low demand: situations 1 and 2 [O1, O2, O3]

AQA 4.2.5.1

• Standard demand: situation 3 [O1, O2, O3]

Learning objectives

• High demand: situations 4 and 5 [O1, O2, O3]

• Describe how insulating materials can become charged. • Know that there are two kinds of electric charge. • Explain these observations in terms of electron transfer.

The situations suggested are:

1. rubber used on aircraft tyres

Learning outcomes

2. anti-static flooring in operating theatres

• Describe how insulating materials can become charged. [O1] • Recall that there are two types of charge and that like charges repel and unlike charges attract. [O2] • Explain how a person can get an electric shock and explain static electricity in terms of electric fields. [O3]

3. cloud-to-ground lightning

Skills development

4. photocopiers 5. paint spraying. Consolidate and apply

• Carry out focused research and describe findings to peers. Resources needed Van de Graaff generator, polythene rods, Perspex rods, dusters, small pieces of paper, balloons, watch glasses; Worksheet 2.1 Key vocabulary attract, conductor, electron, insulator, repel

• The students should then regroup into groups of five so that there is one person from each original group in each new group. [O1, O2, O3]

• Students should use the table on the worksheet as a ‘script’ for sharing their research findings between the members of the group so that they all have the same information by the end of the feedback session [O1, O2, O3]

Teaching and learning

Extend

Engage • Issue the students with a sheet of scrap paper and ask them to write what they understand by the following terms: ‘a conductor’, ‘an insulator’, ‘attraction’ and ‘repulsion’. Follow this by asking students to give an example for each of these terms.

• Alternatively, the words and definitions of the words could be written on separate cards and the students could be asked to match them up.

Ask students able to progress further to do one of the following:

• Explain how a Van de Graaff generator works, using ideas they have met in the lesson. It might be useful to show them a Van de Graaff generator if one is available, or a video clip of one if the equipment is not available. [O1, O2]

• Alternatively, the students could be asked to explain why static charges do not build up on a conductor. Plenary suggestions

Challenge and develop

Show the students a range of demonstrations to illustrate the effect of charging an insulator, for example:

• Charge a polythene rod with a duster and use it to pick up small pieces of paper (circles of paper cut with a hole puncher would be ideal). [O1, O2]

Ideas hothouse: Ask students to work in pairs to list three points about what they know or have learned about static electricity from the lesson today. Then ask the pairs to join together into groups of four and then groups of six to eight to discuss this further and to come up with an agreed list of points. Ask one person from each group to report back to the class. Hot seat: Ask each student to think of a question, using material from the topic. Select someone to put in the hot seat. Ask students to ask their questions and say at the end whether the answer is correct or incorrect.

• Rub a balloon on a jumper and either stick it to the wall or hold it close to someone’s hair. [O1, O2]

• Charge a polythene rod and hold it close to (but not touching) a very thin stream of water from the tap; watch the water ‘bend’. [O1, O2]

• Arrange two watch glasses on top of one another

and rest a Perspex rod on the top of one of them; charging a second Perspex rod with a duster. If the charged rod is held next to the rod resting on the watch glasses, the watch glass on top will rotate due to the repulsion. [O1, O2]

AQA GCSE Physics: Teacher Pack

Chapter 3: Particle model of matter

Check your progress

Percentage 40

you should be able to:

n Use density = mass/volume

n Use particle diagrams to

Total marks

Q. 19 (A02) 6 marks

to calculate density

Q. 18 (A02) 2 marks

➞

n Link the particle model for ➞

n Use the density equation to

Most demanding [Higher Tier]

Q. 17 (A02) 2 marks

n Describe changes of state as

n State that mass is conserved

physical changes

Q. 15 (A02) 2 marks More challenging [Higher Tier]

Q. 14 (A01) 2 marks

➞

Q. 12 (A02) 4 marks

n Describe how heating raises

Q. 11 (A01) 2 marks

➞

Q. 10 (AO1) 1 mark

Going further [Foundation and Higher Tiers]

Q. 9 (A01) 1 mark

n Describe the effect of an

are physical, not chemical, changes because the material recovers its original properties if the change is reversed

➞

the temperature or changes the state of a system but not at the same time

n Explain that internal energy ➞

n Use the specific heat capacity ➞

Q. 8 (A02) 1 mark Q. 7 (A01) 2 marks Q. 6 (A02) 1 mark

n State that when an object changes state there is no change in temperature

n Explain that changes of state

conserve mass

n Describe that heating raises

the temperature of a system

increase in temperature on the motion of the particles

n Explain how changes of state

when substances change state

Q. 13 (A01) 2 marks Q. 5 (A02, A03) 1 mark

equation to calculate the energy required to change the temperature of a certain mass of a substance

➞

n Describe the latent heats of

n State that in the particle

Q. 3 (A02) 1 mark

model the higher the temperature the faster the molecules move

➞

n Use the particle model to ➞

Q. 2 (A01) 2 marks Getting started [Foundation Tier]

Q. 1 (A01) 1 mark

n Recall that gases can be

Student Name

compressed or expanded by pressure changes

explain the effect on temperature of increasing the pressure of a gas at constant volume

➞

AQA GCSE Physics: Teacher Pack

explain why the latent heat of vaporisation is much larger than the latent heat of fusion

n Describe that the ➞

n Use the equation pV = constant to calculate the pressure or volume of a gas at constant temperature

capacity equation to calculate mass, specific heat capacity or temperature change

n Use the particle model to

fusion and of vaporisation

➞ n Use the equation E = mL

is the total kinetic energy and potential energy of all the particles that make up a system

n Use the specific heat

Q. 4 (A02) 1 mark

AQA GCSE Physics: Teacher Pack

solids, liquids and gases with density values in terms of the arrangements of the atoms or molecules

calculate mass and volume

Q. 16 (A01) 6 marks

Marking Grid for End of Chapter 3 Test

communicate ideas about relative densities of different states

temperature of a gas is related to the average kinetic energy of the molecules

n Use the particle model to ➞

explain that increasing the volume of a gas, at constant temperature, can lead to a decrease in pressure

Chapter 6: Waves

Extend • Ask students who are able to use the equation linking velocity, frequency and wavelength to suggest why wave speed is proportional to frequency and wavelength.

Plenary suggestions Ideas hothouse: Ask students to work in pairs to list points about what they know about a particular idea. Then ask the pairs to join together into fours and then groups of six to eight to discuss this further and to come up with an agreed list of points. Ask one student from each group to report back to the class.

When and how to use these pages: Check your progress, Worked example and End of chapter test Check your progress

The big ideas: Ask students to write down three ideas they learned from the topic. Then ask them to share their facts in groups and to compile a master list of facts, with the most important at the top. Ask for ideas to be shared and find out which group(s) agreed.

Check your progress is a summary of what students should know and be able to do when they have completed the chapter. Check your progress is organised in three columns to show how ideas and skills progress in sophistication. Students aiming for top grades need to have mastered all the skills and ideas articulated in the final column (shaded pink in the Student book).

Answers to questions

Check your progress can be used for individual or class revision using any combination of the suggestions below:

Worksheets 6.23.1, 6.23.2 and 6.23.3

• •

Region of spectrum

v (m/s)

Radio waves

3.0 × 10

Microwaves

3.0 × 10

Infra-red

3.0 × 10

Visible light

3.0 × 10

Ultra violet

3.0 × 10

X-rays Gamma rays

l (m)

f (Hz)

1 × 10

3 × 10

1 × 10

3 × 10

1 × 10

3.0 × 10

1 × 10

3 × 10

1 × 10

3 × 10

–2

3.0 × 10

•

–5 –6

Worked example

–9

The worked example talks students through a series of exam-style questions. Sample student answers are provided, which are annotated to show how they could be improved.

1 × 10

–12

1 × 10

3 × 10

•

–3

3 × 10

•

2. 545.45 m 3.

Colour of visible light

Wavelength (m)

Red

630 × 10

Orange

590 × 10

Yellow

560 × 10

Green

490 × 10

Blue

450 × 10

Violet

400 × 10

Frequency

–9

4.76 × 10 Hz

–9

5.08 × 10 Hz

–9

5.36 × 10 Hz

–9

6.12 × 10 Hz

–9

6.67 × 10 Hz

–9

7.5 × 10 Hz

14 14 14 14 14

229

Give students the Worked example worksheet (Teacher Pack CD). The annotation boxes on this are blank. Ask students to discuss and write their own improvements before reviewing the annotated Worked example in the Student Book. This can be done as an individual, group or class activity.

End of chapter test The End of chapter test gives students the opportunity to practice answering the different types of questions that they will encounter in their final exams. You can use the Marking grid provided in this Teacher Pack or on the CD Rom to analyse results. This shows the Assessment Objective for each question, so you can review trends and see individual student and class performance in answering questions for the different Assessment Objectives and to highlight areas for improvement. • • • •

AQA GCSE Physics: Teacher Pack

Ask students to construct a mind map linking the points in Check your progress Work through Check your progress as a class and note the points that need further discussion Ask the students to tick the boxes on the Check your progress worksheet (Teacher Pack CD). Any points they have not been confident to tick they should revisit in the Student Book. Ask students to do further research on the different points listed in Check your progress Students work in pairs and ask each other what points they think they can do and why they think they can do those, and not others

Questions could be used as a test once you have completed the chapter Questions could be worked through as part of a revision lesson Ask Students to mark each other’s work and then talk through the mark scheme provided As a class, make a list of questions that most students did not get right. Work through these as a class.

AQA GCSE Physics: Teacher Pack

230

Student Book answers

Chapter 3: Particle model of matter Lesson 3.1 Density 1a

solid

gas

liquid

The particles in a solid are usually closer together than they are in a liquid or a gas. Therefore, the same mass of material will occupy a smaller volume which makes the density higher.

Density of cork = mass / volume = 3 / 12 3 = 0.25 g / cm

Density of oak = mass / volume 3 = 17 / (2.0 × 3.0 × 4.0) = 0.71 g / cm Density of tin = mass / volume 3 = 364 / (2.5 × 2.5 × 8.0) = 7.3 g / cm

The particles in a gas are far apart. Therefore, the volume of a certain mass of gas is much bigger than the same mass of liquid and solid. This makes the density small.

ρ = m ÷ V = 5400 ÷ 2 = 2700 kg/m

m = ρV = 7700 × 2 = 15 400 kg.

Aluminium is less dense than steel. Therefore, aeroplanes made from aluminium are likely to be much lighter.

Volume = 5 × 4 × 3 = 60 m . m = ρV = 1.3 × 60 = 78 kg.

Cork is less dense than water so it floats. Iron is denser than water, so it sinks.

The mass of the air stays the same but the volume of the air gets less. Since density = mass / volume, this means the density of the air will increase.

1 g / cm means that each cm of the substance will have a mass of 1 g. There are 100 × 100 × 3 3 3 100 = 1000 000 cm in 1 m , so 1 m of the substance will have a mass of 1000 000 g. 3 1000 000 g = 1000 kg, so 1 m of the substance has a mass of 1000 kg – giving a density of 3 1000 kg / m .

There are many errors in the experiment such as not reading the measuring cylinder very accurately. Perhaps your eyes weren’t lined up with the bottom of the meniscus or you weren’t holding the measuring cylinder completely vertically. Also the volume of the necklace is quite small and the measuring cylinder would not be sensitive enough to measure small changes in the volume accurately.

Lesson 3.3 Changes of state 1

Freezing

You could place a block of ice in a container and then place the container on a balance. Record the mass and then wait for all of the ice to melt. Record the mass again and see whether the mass has changed.

Subtract the mass of the empty measuring cylinder 4 to get the mass of the liquid.

Density = mass / volume 3

Sea water: 51.3 / 50 = 1.026 g / cm

AQA GCSE Physics: Teacher Pack

down, so the amount of energy transferred into the surroundings will be less.

5 When you are burned by steam, the steam transfers energy to your skin when it is condensing. This is extra to the energy transferred to your skin when the hot water cools down.

e.g. in cooling systems. Water passing through a car engine can stop the engine from heating up by absorbing some of the thermal energy. The water can absorb lots of energy into its thermal energy store without heating up very much.

Sweat is no colder than your skin. The cooling effect occurs because the sweat evaporates. Not 6a all of the water molecules in the sweat move at the same speed and it is the ones that move the fastest that evaporate. Therefore, the average speed of the molecules decreases as the sweat evaporates and this results in a lower temperature. 6b Lesson 3.4 Internal energy 1

They store kinetic energy because they are moving.

Ek = ½ mv and the particles have the same kinetic energy at the same temperature. This means that the heavy particles are moving slower than the light particles at the same temperature. 8a

The particles store potential energy because they are separated from each other.

The Pacific Ocean has more internal energy than the tea. Each particle in the tea does store more kinetic energy (the tea is hotter) and more potential energy (the particles are further apart). However, there are many more particles in the Pacific Ocean so the total of the kinetic and potential energies stored by the particles in the Pacific Ocean is a much bigger value.

The internal energy increases.

The water cools down, freezes and cools down again. All of this results in a decrease in internal energy.

Lesson 3.5 Specific heat capacity

The fastest moving particles are the ones which evaporate. When they leave the liquid, the

Steam is able to transfer much more energy than water at the same temperature as its internal energy is so much higher.

They move faster (gain kinetic energy) and they get further apart (gain potential energy).

5 There is a larger mass of water in the saucepan than there is in the cup. Therefore, more energy is 6a needed.

Yes it will. The gain in internal energy of the milk is smaller when it heats up. Therefore, the decrease in internal energy will be smaller when it cools

AQA GCSE Physics: Teacher Pack

ΔE = mcΔθ = 0.1 × 4200 × (40 – 10) = 12 600 J

Energy needed = mcΔθ for the copper + mcΔθ for the water = (0.5 × 380 × 10) + (1 × 4200 × 10) = 43 900 J t = E / P = 43 900 / 2000 = 21.95 s = 22 s (to 2 s.f.) I have assumed that all of the energy from the heater has been transferred to the thermal energy stored in the water and in the copper kettle. Copper is a very good conductor of heat – it has a very high thermal conductivity. It also has a low specific heat capacity so not much energy is needed to heat the saucepan up. The temperature of the copper decreases and the temperature of the water increases. Energy is transferred from the mass to the water by heating. Therefore the mass loses internal energy and the water gains internal energy. The final temperature is likely to be closer to 20 °C. The specific heat capacity of water is much larger than that of copper. Therefore for the same mass (both 50g) and the same amount of energy transfer by heating, the temperature change of the copper will be much larger than the temperature change of the water. So the final temperature will be closer to 20 °C.

Lesson 3.6 Latent heat

2 The internal energy of steam at 100 °C is much higher than that of water at the same temperature. The internal energy would also include all of the latent heat of vaporisation. 3

A freezing temperature is not necessarily a cold temperature. Some materials (e.g. tungsten) freeze at thousands of degrees Celsius. We are really only referring to the temperature at which water freezes.

This makes the surface area larger and so more evaporation can take place.

307

average speed of the remaining particles is less (since the fastest ones have left). The temperature is related to the average speed and so the 4 temperature decreases.

e.g. Dry ice changing from a solid to a gas (sublimating). The material involved is carbon dioxide. (Dry ice is solid CO2)

5 3

Volume of cork = 2.0 × 2.0 × 3.0 = 12 cm

You would need to measure the mass of the necklace and the volume of the necklace.

The balance would also be recording the mass of the measuring cylinder.

Acetone: 19.6 / 25 = 0.784 g / cm

You could half fill a measuring cylinder with water. Record the volume of the water. Then place the necklace into the water and make sure it is fully submerged. Record the new volume of the water. The volume of the necklace is the difference between the two volumes you measured. Then you could find the mass of the necklace by placing it on a balance. Repeat the measurements and find an average to reduce the effects of random errors.

Density = mass / volume

Coconut oil: 18.5 / 20 = 0.925 g / cm

The data is only measured to 2 significant figures. Therefore, the answer can only be given to two significant figures. It is incorrect to give any more significant figures as this suggests that the calculation is more accurate than it actually is.

Lesson 3.2 Required Practical: To investigate the densities of regular and irregular solid objects and liquids

Student Book answers

308

The material is changing state. As water turns into steam the particles get further apart. The particles therefore gain potential energy and so they need energy to do this. The particles are only gaining potential energy. The energy in their kinetic energy store remains constant so the temperature remains the same. When particles move from a solid into a liquid they don’t move apart from each other very much. However, when they move from the liquid state to a gas they move apart from each other a great deal and gain much more potential energy. E = mL = 0.1 × 340 000 = 34 000 J Melt the ice at 0 °C: E = mL = 0.2 × 340 000 = 68 000 J Heat the water to 100 °C: E = mcΔθ = 0.2 × 4200 × 100 = 84 000 J

AQA GCSE Physics: Teacher Pack

375 ÂŠ HarperCollinsPublishers Limited 2016 AQA GCSE Physics: Teacher Pack

376 ÂŠ HarperCollinsPublishers Limited 2016

Seismic waves The electromagnetic spectrum

6.10 6.11

Gamma rays and X-rays Ultraviolet and infrared radiation Required practical: Investigate how the amount of infrared radiation absorbed or radiated by a surface depends on the nature of that surface Microwaves Radio and microwave communication Colour Lenses Images and magnification Emission and absorption of infrared radiation

6.13 6.14 6.15

6.17 6.18 6.19 6.20 6.21

Compasses and magnetic fields The magnetic effect of a solenoid Electromagnets in action

7.2 7.3 7.4

Combined Science: Trilogy students do not need to know any of this content.

Combined Science: Trilogy students need to know and understand all content.

Magnetism and magnetic forces

7.1

Combined Science: Trilogy students do not need to know the content of the last section: Changes in velocity, frequency and wavelength, although question 7 is appropriate. Combined Science: Trilogy students do not need to know the content in the following Check your progress boxes: [pink] Explain how to calculate the depth of water using echo sounding [green] Draw a labelled ray diagram to illustrate reflection of a wave at a boundary [green] Describe the range of normal human hearing [blue] Define the term ultrasound [pink] Describe how ultrasound waves can be used for medical and industrial imaging; Explain how P and S waves can be used to deduce information about the structure of the Earth [green] State that each colour in the visible spectrum has its own narrow band of wavelength [blue] Describe that colour filters absorb certain wavelengths and transmit other wavelengths [pink] Explain that the colour of an opaque object depends on which wavelengths are more strongly reflected [green] State that in a convex lens parallel rays of light are brought to a focus at the principal focus [blue] Use ray diagrams to determine the nature of the image formed by a lens [pink] Use ray diagrams to determine the position and magnification of images [green] State that the hotter the body the more radiation it emits in a given time [blue] Explain that a perfect black body absorbs all the radiation incident on it, and does not reflect or transmit any radiation [pink]Explain how the temperature of a body is related to the balance between incoming radiation absorbed and radiation emitted Combined Science: Trilogy students do not need to know the content in Worked example parts 3 and 4 Combined Science: Trilogy students do not need to answer the following questions: 2, 8, 12, 15, 16, 18, 19, 20, 21

Combined Science: Trilogy students do not need to know any of this content.

Combined Science: Trilogy students need to know and understand all content.

Combined Science: Trilogy students do not need to know about: How can a magnetic field be used to produce an electric current? What is a transformer? Note that for Combined Science students, Why is electricity transmitted at high potential differences? is covered in 2.11, not in chapter 7) Combined Science: Trilogy students need to know and understand all content.

Electromagnetism Student Book only Chapter introduction

Chapter 7

Maths skills: Using and rearranging equations Check your progress/Worked example

6.23

End of chapter questions

Temperature of the Earth

6.22

6.16

Reflection, refraction and wave fronts

6.12

Combined Science: Trilogy students need to know and understand all content.

Combined Science: Trilogy students do not need to know any of this content.

Exploring ultrasound

6.9

6.8

6.7

6.6

Required practical: Measuring the wavelength, frequency and speed of waves in a ripple tank and waves in a solid Reflection and refraction of waves Combined Science: Trilogy students do not need to know about reflection, absorption and transmission of sound wave, how to construct ray diagrams for reflection and the law of reflection and, but they do need to know about refraction of electromagnetic waves and how to construct ray diagrams to illustrate refraction (covered again in 6.12). Question 5 is appropriate. Required practical: Investigate the Combined Science: Trilogy students do not need to know any of this content. reflection of light by different types of surface and the refraction of light by different substances Sound waves Combined Science: Trilogy students do not need to know any of this content.

6.5

Combined Science: Trilogy students do not need to know the content in the last section: Echo sounding Combined Science: Trilogy students need to know and understand all content.

Measuring wave speeds

6.4