A solid disk, spinning counter-clockwise, has a mass of 6 kg and a radius of 2 m. If a point on the edge of the disk is moving at 1/3 m/s in the direction perpendicular to the disk's radius, what is the disk's angular momentum and velocity?

1 Answer
Aug 11, 2017

The angular momentum is =2kgm^2s^-1 and the angular velocity is =0.167rads^-1

Explanation:

The angular velocity is

omega=(Deltatheta)/(Deltat)

v=r*((Deltatheta)/(Deltat))=r omega

omega=v/r

where,

v=1/3ms^(-1)

r=2m

So,

omega=(1/3)/(2)=1/6=0.167rads^-1

The angular momentum is L=Iomega

where I is the [moment of inertia

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

So, I=6*(2)^2/2=12kgm^2

The angular momentum is

L=12*0.167=2kgm^2s^-1