- A simple pendulum is another type of simple harmonic oscillator
- The pendulum consists of a string and a bob (a weight, generally spherical) at the end
- The time period of a simple pendulum is given by:
- T = time period (s)
- L = length of string (m)
- g = gravitational field strength (N kg-1)
- Length L is taken from the pivot to the centre of mass of the bob
- Normally, the bob is taken as a point mass, so l is just the length of the string
- The time period of a pendulum does depend on the gravitational field strength, meaning its period would be different on the Earth and the Moon
- The limitation with this formula is that it only works for small angles from the equilibrium point (~10°)
Calculate the time period of a simple pendulum on the Moon, if on Earth it has a time period of 7 s.
g on the moon is 1/6 of that on Earth.