Question

A solid disk, spinning counter-clockwise, has a mass of `1 kg` and a radius of `3 m`. If a point on the edge of the disk is moving at `9 m/s` in the direction perpendicular to the disk's radius, what is the disk's angular momentum and velocity?

Answer 1

Angular Momentum `L=13.5" "kg*m^2/("second")`
Angular Velocity `omega=3" "(rad)/sec`

Explanation:

Angular Momentum `L=I*omega`

where `I=1/2*mr^2" "`Moment of inertia

`I=1/2*(1)(3^2)=4.5" "kg*m^2`

Angular Velocity

`omega=v/r`

`omega=9/3=3" "(radian)/("second")`

Angular Momentum
`L=I*omega`

`L=4.5*3=13.5" "Kg*m^2/sec`

God bless....I hope the explanation is useful.