People usually say that energy is the ability to do work. Another way of saying this is that energy is something that can make things happen. It is easiest to give examples:
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People eat to get their energy. The energy is released when our bodies break down the food. We can use this energy to run, jump and power our bodies.
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Plants get most of their energy from the sunlight falling on their leaves.
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Cars, trucks, buses and planes get their energy to move around by burning petrol or similar fuels.
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Somebody going downhill gets their moving energy from the pull of gravity that keeps all of us on the ground here on planet Earth.
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Electricity is a form of energy that can power light globes, air conditioners, fridges and other devices. Batteries release electrical energy when they are plugged into devices.
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Heat is a form of energy.
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One thing to remember about energy is that it can’t be created or destroyed – only changed from one type of energy into another type. For example, a battery in a torch contains chemical energy. This energy is changed to electrical energy when the torch is switched on. This in turn is changed into light energy and heat energy by the light globe in the torch.