4.1 - Energy Forms
Energy comes in different energy forms
- Heat - The energy a hot object gives out.
- Light - Energy carried as light.
- Sound - Energy carried as sound.
- Kinetic - The energy of a moving object, such as the wind, waves or tides.
- Gravitational potential - The energy an object has because of its height above the ground, such as water held behind a hydroelectric dam.
- Chemical - The energy a substance contains and releases on burning, such as coal, oil, natural gas, wood or food.
- Nuclear - The energy contained in the nucleus of an atom, such as in uranium or plutonium.
- Electrical - Energy carried by an electric current.
- Magnetic - The energy a magnet has.
- Strain potential - The energy an object has when it's been stretched or squeezed out of shape.
Energy forms are not energy resources
- An energy form is one of the ways energy can appear.
- An energy resource is a way of supplying a particular energy form (for example, kinetic energy is a form, while the wind that carries it is a resource).
Energy changes in everyday devices
- Energy is never used up. When a device works, energy is transferred from one form into another.
- Each device has a main energy form going in and the useful energy form coming out:
| Device | Energy change |
|---|---|
| Microphone | Sound → electrical |
| Room heater | Electrical → heat |
| Burning match | Chemical → heat |
These changes can be shown as energy transfer diagrams, where boxes represent energy forms and arrows represent energy transfers.
TermDefinition
Energy formOne of the ways energy can appear.
Energy resourceA source of energy that people can use, such as a fuel, the wind or sunlight.