A tuning fork of frequency 512 Hz is vibrated with sonometer wire and 6 beats per seconds are heard. The beat frequency reduces if the tension in the string is slightly increased. The original freqency of vibration of the string is

Options

A. 506Hz
B. 512Hz
C. 518Hz
D. 524Hz

Answer

A

Explanation

Frequency of tuning fork `(f_(1))=512Hz`
`Deltaf=6` beats per second
`Deltaf=f_(1)-f_(2) or Deltaf=f_(2)-f_(1) implies f_(2)=518 or 506`
On increasing the tension in sonometer wire. Its frequency increases So if in this case beat frequency decreases, this means originally `f_(2) lt f_(1)`
`therefore f_(2)=f_(1)-6=512-6=506Hz`.