A tuning fork arrangement (pair) produces 4 beats/sec with one fork of frequency 288 cps. A little wax is placed on the unknown fork and it then produces 2 beats/sec. The frequency of the unknown fork is
As we learnt in
Beat Frequency -
module of
- wherein
Where are frequency of two wave differ slightly in value of frequency.
The wax decreases the frequency of unknown fork. The possible unknown frequencies are (288+4) cps and (288-4) cps
Wax reduces 284 cps and so beats should increases. It is not given in the question. This frequency is ruled out. Wax reduced 292 cps and so beats should decrease. It is given that the beats decrease to 2 from 4.
Hence unknown fork has frequency 292 cps.
Correct option is 2.
Option 1)
This is an incorrect option.
Option 2)
This is the correct option.
Option 3)
This is an incorrect option.
Option 4)
This is an incorrect option.
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