A cylindrical pipe of length 29.5cm closed at one end is found to be in resonance when a tuning fork of frequency 864Hz is sounded near the open end. Then the mode of vibration of the air in the pipe is (Velocity of sound in air is 340m/s.)

Options

A. 2
B. 4
C. 3
D. 5

Answer

C

Explanation

`n=(v)/(4l) = (340)/(4xx29.5xx10^(-2))`
`=(340xx10^2)/(118)`
`n=228`
`n_1=3xx288=864Hz`
The mode of vibration is 3