Question

when you view the pendulums swing, it shows that at the very top of the swing ke = 0. what does that tell you about the pendulums motion at that point?
the pendulum is momentarily at rest
sample response: if ke = 0, the pendulum is not moving. at the top of the swing, the pendulum must stop for a brief moment.
what did you include in your response? check all that apply.
zero kinetic energy means the pendulum is not moving.
the pendulum stops at the top of the swing.

Explanation:

Kinetic energy (\(KE\)) is given by the formula \(KE=\frac{1}{2}mv^{2}\), where \(m\) is the mass of the object and \(v\) is its velocity. If \(KE = 0\), then either \(m = 0\) (which is not the case for a pendulum) or \(v=0\). A velocity of \(v = 0\) means the object is not moving. For a pendulum, at the top - most point of its swing, it momentarily changes direction. As it changes direction, its speed (and thus velocity) is zero for an instant.

Answer:

• Zero kinetic energy means the pendulum is not moving.
• The pendulum stops at the top of the swing.