56 tunning forks are arranged in a series that each fork given 4 beats/s with previous one. The frequency of last fork is 3 times that fo first. Then frequency of first fork is :

Options

A. 52 Hz
B. 56 Hz
C. 60 Hz
D. 110 Hz

Answer

D

Explanation

Let the frequency of 56 forks be
v, v + 4 , v + 2 `xx`4 .......... V + 55 `xx ` 4.
Now v + 55 `xx` 4 = 3v.
`rArr ` 2v = 220 `rArr " " ` v = 110 Hz.