Q. A pendulum clock is set to give correct time at the sea level. This clock is moved to hill station at an altitude of $2500\ m$ above the sea level. In order to keep correct time of the hill station, the length of the pendulum
A) Has to be reduced
B) Has to be increased
C) Needs no adjustment
D) Needs no adjustment but its mass has to be increased
Explanation
(a) $T = 2\pi\sqrt{\frac{l}{g}}$. At the hill $g$ will decrease so to keep the time period same the length of pendulum has to be reduced
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.