Q. The time period of a simple pendulum is $2\ s.$ If its length is increased 4 times, then its period becomes
A) $16\ s$
B) $12\ s$
C) $8\ s$
D) $4\ s$
Explanation
(d) $T \propto \sqrt{l} \Rightarrow \frac{T_{1}}{T_{2}} = \sqrt{\frac{l_{1}}{l_{2}}} \Rightarrow \frac{2}{T_{2}} = \sqrt{\frac{l}{4l}} \Rightarrow T_{2} = 4\ s$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.