7I Energy changes

Energy

Something that is needed to make things happen or change.

Balanced diet

Eating a variety of foods to provide all the things the body needs.

Diet

The food that you eat.

Joule (J)

The unit for measuring energy.

Kilojoule (kJ)

There are 1000 joules in 1 kilojoule.

Mixture

Two or more substances jumbled together.

Nutrient

Substance needed in the diet.

Weight

The amount of force with which gravity pulls things. It is measured in newtons (N). Your weight would change you went into space or to another planet.

Apparatus

Pieces of equipment.

Gram (g)

A unit for measuring mass.

Mass

The amount of matter that something is made from. Mass is measured in grams (g) and kilograms (kg).

Ratio

A way of comparing two different quantities. Two numbers separated with a colon (:).

Chemical

Food or fuel energy store.

Nuclear

Atomic store in the nuclei of atoms.

Kinetic

Moving energy store.

Thermal

Everything! energy store

Gravitational

Raised above ground energy store.

Elastic

Stretched energy store.

Electromagnetic

Electric and magnetic fields.

Atomic energy

A name used to describe energy when it is stored inside materials. Another name for nuclear energy.

Cells

A source of electricity with a low 'energy' (low voltage). Cells push electrons round a circuit.

Chemical energy

A name used to describe energy when it is stored in chemicals. Food, fuel and batteries all store chemical energy.

Elastic potential energy

A name used to describe energy when it is stored in stretched or squashed things that can change back to their original shapes. Another name for strain energy.

Electricity

A way of transferring energy through wires.

Force

A push, pull or twist.

Gravitational potential energy

A name used to describe energy when it is stored in objects in high places that can fall down.

Kinetic energy

A name used to describe energy when it is stored in moving things.

Law of conservation of energy

The idea that energy can never be created or destroyed, only transferred from one store to another.

Nuclear energy

A name used to describe energy when it is stored inside materials.

Strain energy

A name used to describe energy when it is stored in stretched or squashed things that can change back to their original shapes. Another name for elastic potential energy.

Thermal energy

A name used to describe energy when it is stored in hot objects. The hotter something is the more thermal energy it has.

Transfer

When energy is moved from one store into another or from one place to another we say it is transferred.

Biofuels

Fuels made from plants or animal droppings.

Coal

A fossil fuel made from the remains of plants.

Fossil fuels

Coal, oil and natural gas - all fuels that were formed from the remains of dead plants and animals.

Fuel

A substance that contains a store of chemical or nuclear energy that can easily be transferred.

Gas

One of the states of matter. Does not have a fixed shape or a fixed volume and is easy to squash.

Generate

To produce electricity.

Hydrogen

A gas that burns. It is an element.

Natural gas

A fossil fuel formed from the remains of microscopic dead plants and animals that lived in the sea.

Non-renewable

Any energy resource that will run out because we cannot renew our supplies of it (e.g. oil).

Nuclear fuels

Radioactive metals such as uranium. Nuclear fuels are used in nuclear power stations to generate electricity.

Oil

A fossil fuel formed from the remains of microscopic dead plants and animals that lived in the sea.

Organisms

Living things.

Oxygen

A gas that makes up about 21% of the air.

Renewable

An energy resource that will never run out (e.g. solar power).

Solid

One of the states of matter. Has a fixed shape and fixed volume.

Uranium

A radioactive metal that can be used as a nuclear fuel.

Geothermal power

Generating electricity using heat from rocks underground.

Hydroelectric power

Generating electricity by letting moving water (usually falling from a reservoir) turn turbines and generators.

Photosynthesis

Process that plants use to make their own food. It needs light to work.

Resource

Something needed by an organism. For example, humans need fuels or other energy stores as resources.

Solar cells

Flat panels that use energy transferred by light to produce electricity.

Solar panels

Flat plates that use energy from the Sun to heat water.

Solar power

Generating electricity using energy from the Sun.

Solar power station

A large power station that uses the Sun to heat water to make steam. The steam is used to make electricity in a similar way to fossil fuel or nuclear power stations.

Wind turbine

A kind of windmill that generates electricity using energy transferred by the wind.

Efficiency

A way of saying how much energy something wastes.

Environment

The conditions in a habitat caused by physical environmental factors.