Forces may change the shape of an object. An elastic object, such as a spring, stores elastic potential energy when stretched or squashed. The extension of an elastic object is directly proportional ...

We walk here, we walk there, we walk everywhere. Maybe you’re headed to work or to lunch in a busy city. You’re expending energy, and the exercise is good for you. But what if, on top of that, we ...

JONNY NELSON: Energy. There are lots of different types and lots of different ways of storing it. Chemical energy in a sparkler, elastic potential energy that fires a toy into the air, and many, many ...