Question

When the pendulum bob reaches the mean position, the net force acting on it is zero. Why then does it swing past the mean position?

Answer 1

Answer:

The pendulum bob swing past the mean position because:

When a pendulum's bob is accelerating at its extreme position its velocity is zero. Due to  the restoring toque the bob starts to accelerates towards its mean postion. The  maximum acceleration of the pendulum's bob  is $-w^{2} A$and the the acceleration decreases as $-w^{2} x$  towards the mean position.

The acceleration at the mean position becomes zero but the velocity remains maximum. Hence the bob continues to move and does not stops.Thus it can summarised as the force decreases ,acceleration decreases and velocity increases at slow rate.