What is the moment of inertia of a pendulum with a mass of $2 kg$ that is $7 m$ from the pivot?

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Answer 1 · 2016-12-18T20:00:13

The answer is $I = mr^2$ = 98 $kgm^2$

Assuming you are not being asked to derive the moment of inertia of the pendulum, I will state without proof that this is

$I = mr^2$

where $m$ is the mass hanging from the pendulum and $r$ is the distance from the pivot to the centre of the mass.

With your values, this comes to

$I = 2 xx 7^2$ = 98 $kgm^2$

What is the moment of inertia of a pendulum with a mass of 2 kg2 kg that is 7 m7 m from the pivot?