Q. A tuning fork of frequency 200 Hz is in unison with a sonometer wire. The number of beats heard per second when the tension is increased by 1% is
A) 1
B) 2
C) 4
D) 1/2
Explanation
(a) $\frac{n_{2}}{n_{1}} = \sqrt{\frac{101}{100}} = \left( 1 + \frac{1}{100} \right)^{\frac{1}{2}} = 1 + \frac{1}{200}$
$n_{2} = n_{1} + \frac{n_{1}}{200}$
Number of beats $s^{- 1} = n_{2} - n_{1} = \frac{n_{1}}{200} = \frac{200}{200} = 1$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.