Question

A tuning fork of frequency 440 Hz resonates with a tube closed at one end of length 1.8 cm and diameter 5 cm in fundamental mode. The velocity of sound in air is
A. `336ms^(-1)`
B. `343ms^(-1)`
C. `300ms^(-1)`
D. `350ms^(-1)`

Answer 1

Correct Answer - B
In the fundamental mode of vibration,
`(l+0.3D)=lamda/4=v/(4v)`
`thereforev=4v(l+0.3D)=4xx440(0.18+0.3xx0.05)`
`v=343ms^(-1)`