Question

A tuning fork of unknown frequency produces $4$ beats per second when sounded with another turning fork of frequency $254Hz$ It gives the same fork loaded with wax. The unknown frequency before loading with wax is

• A. $258$
• B. $254$
• C. $250$
• D. Can't be determined

Answer 1

The correct option is A $258$

Given, $Frequency=254Hz,4beats/s$

Let the unknown frequency be $f$,

So, before filling $f-254=4\Rightarrow f=258Hz$

And after filing $254-f=4\Rightarrow f=250Hz$

Thus the required frequency is $258Hz$