Chemistry / Unit 4 Chem 0621 short lesson, about 20 seconds
Energy
Captions available
The idea
Energy is the capacity of a system to supply heat or to do work on its surroundings.
In practice
Inflating a bicycle tire by hand does work, since the pump moves air against the pressure already inside the tire.
Where people slip
"Energy" names a capacity to act, not a substance stored in one fixed location inside an object.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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