A solid disk, spinning counter-clockwise, has a mass of $3 kg$ and a radius of $7/5 m$ . If a point on the edge of the disk is moving at $8/3 m/s$ in the direction perpendicular to the disk's radius, what is the disk's angular momentum and velocity?

Question

1455 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-11-13T10:13:36

The angular momentum is $=28/5kgm^2s^(-1)$
The angular velocity is $=40/12 Hz$

mass $m=3 kg$

radius of solid disc $r=7/5 m$

Velocity on the edge $v=8/3ms^(-1)$

The angular velocity $omega=v/r Hz$

$omega=(8/3)/(7/5)=8/3*5/7=40/21 Hz$

The angular momentum $L=I*omega$

For a solid disc, $I=(mr^2)/2=3*49/25*1/2=147/50kgm^2$

So, angular momentum $L=I*omega=147/50*40/21=28/5kgm^2s^(-1)$

A solid disk, spinning counter-clockwise, has a mass of 3 kg3 kg and a radius of 7/5 m7/5 m. If a point on the edge of the disk is moving at 8/3 m/s8/3 m/s in the direction perpendicular to the disk's radius, what is the disk's angular momentum and velocity?