A simple pendulum and a mass oscillating on an ideal spring both have period T in an elevator at rest. If the elevator now moves downward at a uniform 2 m/s, what is true about the periods of
These two systems?
A) The period of the pendulum would increase but the period of the spring would stay the same.
B) The period of the pendulum would decrease but the period of the spring would stay the same.
C) Both periods would remain the same.
D) Both periods would increase.
E) Both periods would decrease.

Question

Quizplus · Accepted Answer

The period of a simple pendulum depends on the acceleration due to gravity and the length of the pendulum, but not on the horizontal or vertical velocity of the system. Similarly, the period of a mass oscillating on an ideal spring depends on the mass and the spring constant, but not on the system's uniform motion. Therefore, if the elevator moves downward at a uniform speed, neither the gravitational acceleration experienced by the pendulum nor the properties of the spring-mass system change, so both periods remain the same.

A Simple Pendulum and a Mass Oscillating on an Ideal