A solid disk, spinning counter-clockwise, has a mass of $8 kg$ and a radius of $5/2 m$ . If a point on the edge of the disk is moving at $13/4 m/s$ in the direction perpendicular to the disk's radius, what is the disk's angular momentum and velocity?

Question

1291 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2017-01-29T13:01:05

The angular momentum is $=204.2 kgms^-1$
The angular velocity is $=8.17rads^-1$

The angular velocity is

$omega=v/r$

where,

$v=13/4ms^(-1)$

$r=5/2m$

So,

$omega=(13/4)/(5/2)*2pi=13/5pi rad s^-1$

The angular momentum is $L=Iomega$

For a solid disc, $I=(mr^2)/2$

So, $I=8*(5/2)^2/2= 25kgm^2$

$L=13/5pi*25=204.2kgms^(-1)$

A solid disk, spinning counter-clockwise, has a mass of 8 kg8 kg and a radius of 5/2 m5/2 m. If a point on the edge of the disk is moving at 13/4 m/s13/4 m/s in the direction perpendicular to the disk's radius, what is the disk's angular momentum and velocity?