Question

A solid disk, spinning counter-clockwise, has a mass of `4 kg` and a radius of `3/7 m`. If a point on the edge of the disk is moving at `5/9 m/s` in the direction perpendicular to the disk's radius, what is the disk's angular momentum and velocity?

Answer 1

`L = Iw = MR^2*v/R = (4)(3/7)^2*(5/9)/(3/7) = 0.950`

Explanation:

Like linear momentum;
p = mv.

Angular momentum equals the angular component of mass multiplied by the angular velocity,
hence;
L (angular momentum) = I (inertia) x w (angular velocity).

Inertia of a solid disk = `MR^2`, where R = radius, and M = mass of disk.

Angular velocity equals tangential velocity divided by radius.