Question

Stems of 2 vibrating tuning forks A and B are touched to the wooden box of a sinister.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.

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

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

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

Answer 1

1) (sonometer) The paper rider vibrates with the tuning fork A

2) Resonance

3) observe the string vibrating with large amplitudes and throws the paper rider away. Even the sound we hear is louder now. This happens when the natural frequency of the vibrating string is equal to the frequency of the tuning fork. When the natural frequency of a body undergoing forced vibrations is equal to the frequency of forced vibrations the body vibrates with greater amplitude. This is known as resonance