Divi test

Energy transformations

The conservation of energy:
“Energy can’t be created or destroyed but only changed from one form into another.” Explain the energy changes for the following situations:

Answers:

1) GPE → KE → sound + thermal
GPE = gravitational potential energy (energy because of an object’s height/position) KE = kinetic energy (movement energy)

Note: the stone is high up so it has GPE, it falls so it is moving (KE), then hits the floor/ground which you can hear and heat will be lost to the surroundings.

2)  Electrical → light + heat

Note: light bulbs get hot as a lot of energy is lost as heat.

3)  Chemical → electrical → KE

4)  Chemical → electrical → KE

Note: batteries (cells) are a store of chemical energy which is converted into electricity in the wires of the device.

Key point: heat is always lost in an energy transformation.