Question

An air column in pipe, which is closed at one end, will be in resonance with a vibrating tuning fork of frequency `264 Hz` if the length of the column in `cm` is :
A. 31.25
B. 62.5
C. 93.75
D. 125

Answer 1

Correct Answer - A::C
The wavelengths possible in an air column in a pipe which has one closed end is
`lamda = (4l)/((2n+1))`
so, `c = v lamda rArr 330 = 264 xx (4l)/(2n+1)`
as it is in resonance with a vibrating tuning fork of frequency `264 Hz`
`l =(330 xx(2n+1))/(264 xx4)`
For `n = 0,l = 0.315 m = 31.25 cm`
For `n=1,l=0.9375 m=93.75 cm`.