As the distance from equilibrium decreases, in what way is the magnitude of the force on an object that is undergoing simple harmonic motion affected? a. it increases. b. it decreases. c. it remains the same.

The correct answer is B. The force decreases.

Simple harmonic motion is a to and fro motion about the equilibrium position, with the restoring force proportional to the displacement and it is always directed towards the mean position.

Mathematically, the force F is given by,

Here, x is the displacement from the equilibrium position and k is the force constant. The negative sign indicates that the direction of the force is always directed towards the equilibrium position, opposite to the direction of the displacement from the equilibrium position.

Thus, as the displacement from the equilibrium position decreases, the force acting on the body also decreases.