# What is the moment of inertia of a pendulum with a mass of 3 kg that is 5 m from the pivot?

The moment of inertia for a single mass $m$, placed $r$ metres from the pivot, is given by:
$I = m {r}^{2} = 3 \times {5}^{2} = 75$ $k g {m}^{2}$