Question

A tuning fork produces 4 beats per second when sounded with a sonometer of vibrating length 48 cm. It produces 4 beats per second also when the vibrating length is 50 cm. What is the frequency of the tuning fork?

Solution

Correct option is

196 Hz

 

Let V1 be the frequency of the wire when its vibrating length is L1 = 48 cm and V2 when L2 = 50 cm. Since  If V is the frequency of the tuning fork, then

                   

Which gives V = 196 Hz.

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Q8

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