The motion of a simple pendulum is very close to Simple Harmonic Motion (SHM).
SHM results whenever a restoring force is proportional to the displacement, a relationship often known as Hooke’s Law when applied to springs. Where F is the restoring force, k is the spring constant, and x is the displacement.
Find out how the period of oscillation varies in a pendulum – does it depend on the length of the pendulum or the mass of the bob? Will it swing faster or slower when transferred to Moon?