Question

beating a drum represents what kind of energy conversion?
electrical to mechanical
mechanical to sound
chemical to electrical

Explanation:

When beating a drum, the action of hitting the drum (a mechanical action, so mechanical energy) causes the drum to vibrate and produce sound (sound energy). So the energy conversion is from mechanical to sound. The other options: electrical to mechanical would involve something like an electric motor, and chemical to electrical is like a battery, neither of which apply here.

Answer:

B. mechanical to sound