A simple pendulum consists of a ball of mass m suspended from the ceiling using a string of length L. The ball is displaced from its equilibrium position by a small angle $\theta$. What is the magnitude of the restoring force that moves the ball toward its equilibrium position and produces simple harmonic motion?
A)kx
B)mg
C)mg(cos $\theta$)
D)mg(sin $\theta$)
E)mgL(sin $\theta$)

Question

Quizplus · Accepted Answer

The restoring force that moves the ball toward its equilibrium position can be found by resolving the weight of the ball into two components: mgcosθ, acting along the string and mg sinθ perpendicular to the string. The component of weight perpendicular to the string does not contribute to restoring force. Therefore, the restoring force is the component mg sinθ, which is equal to mg(sinθ) = mg(sinF1F1F1S1θF1F1F10).

A Simple Pendulum Consists of a Ball of Mass M θ\thetaθ

A Simple Pendulum Consists of a Ball of Mass M $\theta$