Question

What is the angular momentum of a rod with a mass of `8 kg` and length of `4 m` that is spinning around its center at `8 Hz`?

Answer 1

The angular momentum is `=536.2kgm^2`

Explanation:

The angular momentum is `L=Iomega`

where `I` is the moment of inertia

and `omega` is the angular velocity

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

`I=1/12*mL^2`

The mass of the rod is `m=8kg`

The length of the rod is `L=4m`

Therefore, the moment of inertia is

`L=1/12*8*4^2= 10.67 kgm^2`

The frequency is `f=8Hz`

The angular velocity is `omega=2*pi*f=16pi`

Then,

The angular momentum is

`L=Iomega=10.67*16pi=536.2kgm^2`