Question

An unknown frequency source $X$, produces $8$ beats with another source of frequency $270Hz$. The frequency of source $X$ will be ?

• A. $282Hz$
• B. $262Hz$
• C. $242Hz$
• D. $258Hz$

Answer 1

The correct option is B $262Hz$

Given, a known frequency of $270Hz$ and an unknown frequency source X producing $f_{beat}=8Hz$.

We have to find the unknown frequency.

Let us suppose that unknown frequency is $f$.

We have $|f-270|=8Hz$

So, either $f=(270+8)Hzorf=(270-8)Hz$

Both of them are eligible answers, but we have only 262 Hz in the question.

So, B is the correct answer.