Question

A tuning fork A produces $2$ beats per second when sounded with a tuning fork of frequency $200Hz$. When A is loaded with wax the beats stop. What is the frequency of fork A?

• A. $198Hz$
• B. $202Hz$
• C. $204Hz$
• D. $196Hz$

Answer 1

Answer: (B)

$202Hz$

There are $2$ beats $persecond$

$\therefore f_1-f_2=2$

$\Rightarrow 200-f_2=\pm 2$

$f_2=200\pm 2$

$f_2=202$ or $f_2=198$

When loaded with wax the beats stop since the frequency decreases on loading.

$\therefore f_2=202Hz$