For a pendulum, when is the gravitational potential energy (GPE) greatest and kinetic energy (KE) least?

Question

A. At the lowest point of the pendulum’s swing.

B. At the highest point of a back swing.

C. When the pendulum is halfway to its highest point on the backward swing.

D. When the pendulum is halfway down from its highest point on the frontward swing

Answer 1

B is correct

Answer 2

The two above me have already given you the answer but not the explanation.

Now, recall the formulas for GPE and KE:

GPE = mgh

KE = 0.5 mv^2

GPE has 'h' (height) in it, so when the pendulum is at the highest position (above the ground), it has maximum h, so maximum GPE.

Also when it is at maximum height, the pendulum momentarily stops before changing direction. (it was going up, then it stops, changes direction and starts to decend). Because it stops, it has zero velocity at that point. v = 0 and as KE has 'v' in it, it also becomes zero.

Answer - B

Answer 3

B. At the highest point of a back swing,