A solid disk, spinning counter-clockwise, has a mass of 1 kg and a radius of 5 m. If a point on the edge of the disk is moving at 3 m/s in the direction perpendicular to the disk's radius, what is the disk's angular momentum and velocity?

1 Answer
Mar 17, 2017

The angular momentum is =47.1kgm^2s^-1
The angular velocity is =3.78rads^-1

Explanation:

The angular velocity is

omega=v/r

where,

v=3ms^(-1)

r=5m

So,

omega=(3)/(5)*2pi=3.78rads^-1

The angular momentum is L=Iomega

where I is the moment of inertia

For a solid disc, I=(mr^2)/2

So, I=1*(5)^2/2=25/2kgm^2

L=25/2*3.78=47.1kgm^2s^-1