A mass is suspended vertically from a spring so it is at rest at the equilibrium position. The mass is pulled a short distance straight down and released so that it oscillates about the equilibrium position. The acceleration of the mass is zero when the mass is
A) at its highest point.
B) at the equilibrium position.
C) at its lowest point.
D) somewhere between the equilibrium point and maximum extension.

Question

Quizplus · Accepted Answer

At the equilibrium position, the spring force and weight of the mass are equal and opposite, resulting in zero net force and zero acceleration. At maximum extension or compression, the forces are not balanced and acceleration is non-zero. Therefore, the acceleration of the mass is zero when it is at the equilibrium position.

A Mass Is Suspended Vertically from a Spring So It