A sonometer is set on the floor of a lift. When the lift is at rest, the sonometer wire vibrates with fundamental frequency 256 Hz. When the lift goes up with acceleration a `=(9g)/(16)` , the frequency of vibration of the same wire changes to

Options

A. 512 Hz
B. 320 Hz
C. 256 Hz
D. 204 Hz

Answer

B

Explanation

`n_2/n_1 = sqrt(g_2/g_1) = sqrt((a+g)/(g)) = sqrt(((9g)/(16)+g)/(g))`
`=sqrt((25g)/(16g)) = 5/4`
`n_2=5/4 n_1`
`=5/4xx256=320Hz`