Question

1. which situation shows potential energy changing into kinetic energy?

a) a book falling off a shelf
b) a stretched rubber band
c) a child climbing up a ladder
d) a battery stored in a drawer

Explanation:

• Option A: When a book is on a shelf, it has gravitational potential energy. As it falls, its height decreases (so potential energy decreases) and its speed increases (so kinetic energy increases). This is a clear case of potential energy (gravitational) changing into kinetic energy.
• Option B: A stretched rubber band has elastic potential energy. But just being stretched (without any motion to show conversion to kinetic energy) does not represent a conversion from potential to kinetic energy.
• Option C: A child climbing up a ladder is doing work against gravity. The child's height is increasing, so gravitational potential energy is increasing (not converting from potential to kinetic).
• Option D: A battery stored in a drawer has chemical potential energy. There is no motion (no kinetic energy change) indicated here for a conversion from potential to kinetic energy.

Answer:

A. A book falling off a shelf