Question

describing the energy of a pendulum
determine how potential and kinetic energy changes at each position of the pendulum as the ball swings from a to e.
position a: dropdown
position b: dropdown
position c: dropdown with checkmark
position d: dropdown
position e: dropdown
options (partially visible): is all kinetic, is all potential, is losing kinetic and gaining potential, is losing potential and gaining kinetic

Explanation:

Position A:

At position A (the highest point on the left), the pendulum bob has maximum height and zero velocity. Potential energy (PE) depends on height ($PE = mgh$) and kinetic energy (KE) depends on velocity ($KE=\frac{1}{2}mv^2$). With $v = 0$, KE is zero, and PE is maximum (all energy is potential).

As the bob moves from A to C, it descends (losing height, so losing PE) and gains speed (gaining KE). At position B (between A and C), it is in the process of converting PE to KE, so it is losing potential and gaining kinetic energy.

Position C is the lowest point of the pendulum's swing. Here, the height is minimum (so PE is minimum) and the velocity is maximum (since it has accelerated down). Thus, all the energy is kinetic (KE is maximum, PE is minimum).

Answer:

is all potential

Position B: