An organ pipe closed at one end restonates with a tuning fork of frequencies 180 Hz and 300 Hz it will also resonate with tuning fork of frequencies

Options

A. 360 Hz
B. 420 Hz
C. 480 Hz
D. 600 Hz

Answer

B

Explanation

Let resonating frequencies are `N_(1)v and N_(2)v " where " N_(1) and N_(2)` are integers and v is fundametal frequency .
Here ` N_(1)v= 180 Hz and N_(2)v = 300 Hz`
` N_(1)/N_(2) = (180)/300 = 18/30 = 3/5`
`N_(1) = 3 and N_(2) = 5`
3v = 180
` Rightarrow v = 180/3 = 60 Hz`
Possible harmonics in the case of closed end organ pipe are 1,3,5 7,9,11,13 ...
The corresponding frequencies are 60 Hz, 180 Hz, 300 Hz, 420 Hz