A pendulum of length L is suspended from the ceiling of an elevator. When the elevator is at rest the period of the pendulum is T. How does the period of the pendulum change when the elevator
Moves upward with constant velocity?
A) The period increases if the upward acceleration is more than g/2 but decreases if the upward acceleration is less than g/2.
B) The period increases.
C) The period decreases.
D) The period does not change.
E) The period becomes zero.

Question

Quizplus · Accepted Answer

The period of a pendulum, $T = 2\pi\sqrt{\frac{L}{g}}$, depends only on the length of the pendulum and the acceleration due to gravity, g. When the elevator moves upward with constant velocity, there is no change in the acceleration due to gravity experienced by the pendulum, hence the period remains the same.

A Pendulum of Length L Is Suspended from the Ceiling