A solid disk, spinning counter-clockwise, has a mass of 11kg and a radius of 47m. If a point on the edge of the disk is moving at 85ms in the direction perpendicular to the disk's radius, what is the disk's angular momentum and velocity?
1 Answer
Dec 26, 2016
The angular momentum of the disk is
Explanation:
Angular momentum is given by
The moment of inertia of a solid disk is given by
We are given that
ω=vr=85ms47m
⇒ω=145rads
This is the angular velocity.
I=12mr2=12(11kg)(47m)2
⇒I=8849kgm2
This is the moment of inertia.
We can now calculate the angular momentum:
→L=Iω=(8849kgm2)⋅(145rads)
⇒→L=17635kgm2s
⇒→L≈5kgm2s