A solid disk, spinning counter-clockwise, has a mass of #3 kg# and a radius of #3 m#. If a point on the edge of the disk is moving at #8 m/s# in the direction perpendicular to the disk's radius, what is the disk's angular momentum and velocity?

1 Answer
Oct 25, 2016

Answer:

The disc angular momentum is #36 kg m^2s^(-1)#
And the angular velocity is #(8/3) (rad)/s#

Explanation:

The angular momentum is given by #L=I×omega#
Where #I= #moment of inertia
And #omega=#angular velocity

The moment inertia of a disc is given by #I=(mr^2)/2#
where #m=# mass of the disc
And #r=#radius of the disc

Also we use the formula #v=r.omega#

So #omega=v/r=8/3 rad/s#

#I=3.3^2/2=27/2 kg m^2#

And the angular momentum is #L=27/2.(8/3)=36 kg m^2s^(-1)#