The length of an open organ pipe is twice the length of another closed organ pipe. The fundamental frequency of the open pipe is 100 Hz. The frequency of the third harmonic of the closed pipe is

Options

A. 100 Hz
B. 200 Hz
C. 300 Hz
D. 150 Hz

Answer

C

Explanation

Let, length of open organ pipe `=I_(a)` and length of closed organ pipe `=I_( c)`
and `I_(a) = 2l_( c)`
Fundamental frequency of the open pipe, `v_(0) = 100 Hz`
Also, `v_(0) =v/(2l_(0)) = 100`
`v/l_(0) = 200, v/(2l_(0))= 200` or `v/l_(c ) = 400`
Fundamental frequency of closed organ pipe
`v_( c) =v/(4l_( c)) = 400/4 = 100 Hz`