If I were to set my chair on top of my desk, it would be dangerous, as well as inconvenient. If I were to sit in my chair while it was set on my desk, it would be inconvenient and even more dangerous.

Solve a basketball jump physics problem by tracking how mechanical energy changes from takeoff to peak height. This video explains kinetic energy, gravitational potential energy, and energy ...

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 ...