Question

A pendulum has 330 J of potential energy at the highest point of its swing. How much kinetic energy will it have at the bottom of its swing?

Answer 1

The pendulum has a kinetic energy of 330 J at the bottom of its swing.

when a pendulum oscillates, the energy at its highest point is wholly potential, since it is momentarily at rest at the highest point. The pendulum experiences acceleration which is directed towards the mean position, as a result of which its speed increases. It has maximum speed at the point which is at the bottom of its swing.

As the pendulum swings from the highest to the lowest point, the potential energy at the highest point is converted into kinetic energy.

If air resistance can be neglected, one can apply the law of conservation of energy, which states that the total energy of a system remains constant.

In this case, the potential energy of 330 J at the highest point would be equal to the kinetic energy at the bottom point.

Therefore, the kinetic energy at the bottom of its swing will be 330 J.