Question

The diagram above shows a wire stretched over a sonometer. Stems of two vibrating tuning forks A and Bare touched to the wooden box of the sonometer. It is observed that the paper rider (a small piece of paper folded at the centre) present on the wire flies off when the stem of vibrating tuning fork B is touched to the wooden box but the paper just vibrates when the stem of vibrating tuning fork A is touched to the wooden box.

1) Name the phenomenon when the paper rider just vibrates.

2) Name the phenomenon when the paper rider flies off.

3) Why does the paper rider fly off when the stem of tuning fork B is touched to the box?

Answer 1

1) Vibration (The frequency of fork is close to the natural frequencies of vibrating wire).

2) Resonance

3) The paper rider flies off because the natural frequency of vibration of wire matches the frequency of the tuning fork.