They can be used to change the form of energy.

All that happens is a change in the form of energy.

Heat is a form of energy and not a physical substance.

"You have to apply heat or some other form of energy to get the water out."

The forms of energy are often named after a related force.

Dinosaurs are still with us in the form of energy.

However, some forms of energy are more useful than others.

Discussion question: What new forms of energy do you think will be used in the future?

Is it a form of energy or just a "force".

Yet we do not take one measure in the form of renewable energy which would certainly provide jobs.