Question

Two tuning forks, with natural frequency of 340 Hz each, move relative to a stationary observer. While one fork moves away from the observer, the other moves towards him, with the same speed. The observer hears beats of frequency 3Hz. The common speed, of the two forks, expressed as a fraction of the speed of sound (v), is (nearly)

(1) v/114

(2) v/227

(3) v/284

(4) v/341

Answer 1

(2) v/227

Let the common speed of the two forks be (v/x).

The apparent frequency, of the fork moving away, is

The apparent frequency of the fork, moving towards, is