Question

A vibrating tuning fork is placed over the mouth of a burette filled with water. The tap of the burette is opened and the water level gradually starts falling. It is found that the sound from the tuning fork becomes very loud for a particular length of the water column.

1. Name the phenomenon taking place when this happens.
2. Why does the sound become very loud for this length of the water column?

Answer 1

1. The phenomenon is resonance.
2. At this air-column length, its natural frequency becomes equal to the frequency of the tuning fork. Therefore, the air column vibrates with large amplitude and produces a loud sound.