In the picture of the pendulum below, which comparison is true of the pendulum bob when it is at points 1 and 2?

(1 point)
Responses

The pendulum has its highest kinetic energy at points 1 and point 2
The pendulum has its highest kinetic energy at points 1 and point 2

The pendulum has its highest potential energy at point 1 and point 2
The pendulum has its highest potential energy at point 1 and point 2

The potential energy does not change when the bob is swinging from point 1 to point 2.
The potential energy does not change when the bob is swinging from point 1 to point 2.

It has the lowest potential energy at points 1 and 2.
It has the lowest potential energy at points 1 and 2.

1 answer

In a pendulum, the energy changes between kinetic energy (KE) and potential energy (PE) as it swings:

  • At the highest points (like point 1 and point 2), the pendulum bob is momentarily at rest, meaning it has maximum potential energy and minimum kinetic energy.
  • At the lowest point in its swing (typically the midpoint), the bob has maximum kinetic energy and minimum potential energy.

Given these principles, let's evaluate the provided statements:

  1. The pendulum has its highest kinetic energy at points 1 and point 2: This is FALSE. The kinetic energy is lowest at the highest points.

  2. The pendulum has its highest potential energy at point 1 and point 2: This is TRUE. Potential energy is highest at the peaks of the swing.

  3. The potential energy does not change when the bob is swinging from point 1 to point 2: This is FALSE. Potential energy changes as the bob moves up and down.

  4. It has the lowest potential energy at points 1 and 2: This is FALSE, as potential energy is highest at these points.

Therefore, the correct answer is: The pendulum has its highest potential energy at point 1 and point 2.