Q. A simple pendulum has time period $T.$ The bob is given negative charge and surface below it is given positive charge. The new time period will be
A) Less than $T$
B) Greater than $T$
C) Equal to $T$
D) Infinite
Explanation
(a) In this case time period of pendulum becomes
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$T^{''} = 2\pi\sqrt{\frac{l}{\left( g + \frac{qE}{m} \right)}}$
$\Rightarrow T^{''} < T$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.