Question

A tank is filled with smoke. Inside the tank are two speaker elements. When a sound is played at the right frequency and volume, the tank eventually clears. Describe the process that occurs.

Answer 1

Volume is the perception of loudness from the intensity of sound wave. Thus right volume implies right intensity and so right frequency of vibration.

Right frequency is the frequency of sound matching with the natural frequency of smoke particles. Resonance takes place and at the resonance frequency the smoke particles absorbs maximum energy from sound waves and their amplitude of vibration increases. The smoke particles vibrate strongly and leave the tank or may move to the walls, leaving the tank clear.

The process which results in clearing of tank is thus RESONANCE.