Question

What is the angular momentum of a rod with a mass of `4 kg` and length of `9 m` that is spinning around its center at `18 Hz`?

Answer 1

The angular momentum is `=3053.6kgm^2s^-1`

Explanation:

The angular momentum is `L=Iomega`

where `I` is the moment of inertia

The mass of the rod is `m=4kg`

The length of the rod is `L=9m`

The moment of inertia of a rod, rotating about the center is

`I=1/12*mL^2`

`=1/12*4*9^2= 27 kgm^2`

The angular velocity is

`omega=2pif=2pi*18=(36pi)rads^-1`

Therefore,

The angular momentum is

`L=27*36pi=3053.6kgm^2s^-1`