Question

An organ pipe is closed at one end has fundamental frequency of 1500 Hz. The maximum number of overtones generated by this pipe which a normal person can hear is
A. `14`
B. `13`
C. `6`
D. `9`

Answer 1

Correct Answer - C
Critical hearing frequency in Nth mode then frequency of vibration `n=((2N-1)v)/(4l)=(2N-1)n_1`
(where `n_1=`fundamental frequency of vibration)
Hence `20,00=(2N-1)xx1500impliesN=7.1=7` Also, in closed pipe
Number of over tones`=`(No. of mode of vibration)`-1=7-1=6`.