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

1 Answer
Jul 17, 2017

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

Explanation:

The angular velocity is

omega=(Deltatheta)/(Deltat)

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

omega=v/r

where,

v=2ms^(-1)

r=2m

So,

omega=(2)/(2)=1rads^-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*(2)^2/2=2kgm^2

The angular momentum is

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