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?

Answer 1

Kinetic Energy (KE) is defined as 1/2mv²

If 1/2mv² = 0 the either m = 0 (meaning the pendulum has no mass which isn't likely), or that the velocity (v) = 0. So if the velocity is zero, it is instantaneously stopped. Think about the fact that the velocity is going one direction (we'll say that's the positive direction or positive velocity) and slows as it reaches the top of its swing then reverses direction so it is now going in the opposite or negative direction with negative velocity. Then somewhere between a positive velocity and a negative velocity it had to pass through zero. That was at the top of its swing. So you could say it was instantaneously stopped (no motion) at that point..

Answer 2

Kendi

Apply the equation KE = 1/2mv²

you know that for any real object, mass cannot be zero so for KE to be zero, v must be zero. The bob is at rest.

Mr A