The fundamental frequency of an open organ pipe is 300Hz. The first overtone of this has same frequency as that of first overtone of a closed organ pipe. If speed of sound is 330m/s, then the length of closed of organ pipe will be

Options

A. 41cm
B. 37cm
C. 31cm
D. 80cm

Answer

A

Explanation

For open pipe `n=v/(2l)` where `n_0` is the fundamental frequency of open pipe
`thereforel=v/(2n)=330/(2 times 330)=11/20`
As freq. of 1st overtone of open pipe= freq. of 1st overtone of closed pipe
`therefore 2 v/(2l)=3 (v.)/(4l.)implies l.=(3l)/4=3/4 times11/20=41.25cm`