When you view the pendulum’s swing, it shows that at the very top of the swing ke = 0. what does that tell you about the pendulum’s motion at that point?

What it tell us about the pendulum’s motion at that point is that

Kinetic Energy (KE) is known.as 1/2mv square

If 1/2mv square is equal to 0

then

mass m = 0

This shows that the pendulum has no mass or

velocity (v) = 0. meaning the velocity is zero, it is stopped at once.

The velocity that is moving one way or direction can be said to be in a positive direction or positive velocity.

It does slows down when it reaches the top of its swing then move again back to the opposite direction making it to move in the opposite or negative direction with negative velocity. This make a positive velocity and a negative velocity which has pass through to be zero.

Conclusively, a pendulum at the top of its swing, when it stops moving does not have any speed and therefore it has no kinetic energy.

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