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The magnetic effect of a magnet spreads out from the poles and is called the Magnetic Field. You can investigate the field around a magnet using iron filings to show the pattern or using a plotting compass to follow the direction

(start from one corner of the magnet and slowly move the plotting compass in the direction the needle points to bring you round to the other pole).

See how the arrows come OUT of the North and go INTO the South pole.

To attract a compasses North pole, the field at the Arctic must be a South.

The churning iron in Earth’s core creates its own magnetic field, as if there were a huge bar-magnet inside Earth.

This is how compasses work for navigation. The needle of a compass is a tiny bar-magnet which lines up with Earth’s magnetic field lines so its own tiny North pole always points to magnetic North, roughly the same direction as the actual North pole of the planet.

When an electric current flows in a wire, a circular magnetic field is produced around the wire. Winding the wire into a coil reinforces the magnetism created, and an iron core through the wire coil will make the magnetism even stronger.

The lines from each coil link up

This is an electromagnet. You can investigate its strength by seeing how many paperclips it holds for more or less times the wire is wrapped round.

Electromagnets also attract and repel other magnets. This is how electric motors work, as well as speakers and ‘vibrate’ mechanisms in a mobile phone.

This wire feels an upward force from the magnets This wire feels a downward force from the magnets

The coil & magnet attract and repel

Groups – are the columns / Periods – are the rows.

Elements in the same group have similar properties. i.e. all Group 1 metals react violently with water. The symbol for an element can be a single capital letter or a capital and a lower case letter. The symbols don’t always match the name of the element – usually this is because the symbol is based on the name in Greek or Latin.

All Group 1 metals are:

Known as alkali metals. Silvery-coloured metals Soft and can be easily cut Reactivity decreases as you go down the group. change as you go down the group.

Group 7:

1. 2. Known as halogens. Reactivity decreases as you go down the group.

All Group 1 metals have a very high reactivity and the reactivity increases

Group 8:

1.

2.

3. Known as Noble gases. All Noble gases are inert (unreactive). Reactivity does not down the group.

Elements are made up of only 1 type of atom. The periodic table is a list of all the elements that we know. If a substance can be broken down into simpler parts, it cannot be an element.

Elements Mixtures Compounds

When two or more elements are chemically joined together, we call this a compound. Compounds are different to mixtures. Mixtures are not chemically joined, can be easily separated and do not have a fixed composition. Compounds are chemically joined, can’t be easily separated and have a fixed composition.

Chemical formulae tell you which elements are in a compound, and how many of that element there are.

A polymer is a large molecule made up of many small, repeating units (monomers).

They join together through polymerisation reactions.

When a wave OSCILATES, ENERGY is transferred (moved) from one end of the wave to the other. MATTER particles do not move along the wave.

Microphones work by converting SOUNDWAVES into KINETIC and then ELECTRICAL ENERGY. Loudspeakers do the opposite, they convert ELECTRICAL ENERGY, into KINETIC ENERGY and GENERATE SOUNDWAVES.

ULTRASOUND are waves with a very high PITCH. They can be used to travel through the body (harmlessly) and reflect off of objects inside. The ULTRASOUND waves can then be converted into images.

The ELECTROMAGNETIC SPECTRUM shows a range of waves each with a different PITCH (FREQUENCY). The length of the waves also changes, this is called WAVELENGTH. Each part of the spectrum has a different use.

Waves exist in two form LONGITUDINAL (for example soundwaves) and TRANSVERSE (all of the EM spectrum).

When EARTHQUAKES occur they produce SEISMIC waves called S and P waves.

P (Primary) waves are LONGITUDINAL and can travel through LIQUIDS and SOLIDS. They are detected at the other side of the Earth. S (Secondary) waves are TRANSVERSE. These waves can only travel through SOLIDS so do not pass through the LIQUID OUTER CORE of the Earth.

Superposition

This occurs when two waves match-up and are ‘sat on top’ of each other. Superposition can be CONSTRUCTIVE where the wave is AMPLIFIED or DESTRUCTIVE which reduces or cancels the wave. This is the basis of noise cancelling headphones.

What is a Natural Hazard

A natural hazard is a natural process which could cause death, injury or disruption to humans, property and possessions.

Meteorological Hazard

These are hazards caused by weather and climate.

Formation of Tropical Storms

Coriolis Force

Due to the Earth’s curved surface and rotation, the Coriolis force causes winds to bend and tropical storms to spin.

Northern Hemisphere: winds curve to the right = spin anticlockwise. Southern Hemisphere: winds curve to

the left = spin clockwise.

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The sun’s rays heats large areas of ocean in the summer and autumn. This causes warm, moist air to rise over the particular spots

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Once the temperature is 27°C, the rising warm moist air leads to a low pressure. This eventually turns into a thunderstorm. This causes air to be sucked in from the trade winds.

With trade winds blowing in the opposite direction and the rotation of earth involved (Coriolis effect), the thunderstorm will eventually start to spin.

When the storm begins to spin faster than 74mph, a tropical storm (such as a hurricane) is officially born.

With the tropical storm growing in power, more cool air sinks in the centre of the storm, creating calm, clear condition called the eye of the storm.

When the tropical storm hits land, it loses its energy source (the warm ocean) and it begins to lose strength. Eventually it will ‘blow itself out’.

Distribution of Tropical Storms

They are known by many names, including hurricanes (North America), cyclones (India) and typhoons (Japan and East Asia). They all occur in a band that lies roughly 5-15°C either side of the Equator.

Conditions required for a tropical storm

Ocean temp > 26°C Water depth 60-70meters Location between 5°C and 30°C north and south of the equator. Season: late summer, early autumn

Effects and Responses

Climate change

Changing pattern of Tropical Storms

Scientist believe that global warming (heating of the world) is having an impact on the frequency, strength and distribution of tropical storms. This may be due to an increase in ocean temperatures.

Primary Effects

High rainfall, storm surges = flooding (coastal and flood plains) Infrastructure destroyed Buildings destroyed Contaminated water supplies Communication cables destroyed by high winds Homelessness Deaths

Secondary Effects (because of the primary)

Disease spread Food shortages Blocked roads makes it harder to evacuate further Loss of tourism / businesses Landslides due to heavy rainfall Cost to the economy

Immediate Responses (hours-days) Long-term Responses (months – years)

Evacuation before the storm Rescue survivors and treat injured Prevent spread of disease – cover dead bodies Temporary shelters Supplied for food, water, medicine Aid workers e.g. Red Cross

Rehouse those who were made homeless Rebuild / repair Improve structural design for future tropical storms Improve forecasting Improve flood defences Restore food, water supplies, reconnect communication links