Rotational kinetic energy problem

[blackbyron]

Homework Statement

A solid sphere with a mass 8.2kg and radius 10cm is sliding along a frictionless surface with a speed 5.4m/s while at the same time spinning. The sphere has 0.31 of its total kinetic energy in translational motion. How fast is the sphere spinning?

Homework Equations

KAe = (1/2)(I)(W)^2

The Attempt at a Solution

The problem is that the rotational kinetic energy is unknown, but I found that the inertia is .0328kgm^2

How do I find the rotation kinetic energy so I can solve for w?

 

[SteamKing]

In the relevant equations, you have left out the formula for calculating the kinetic energy due to translation of the sphere at the given speed.

 

[blackbyron]

In the relevant equations, you have left out the formula for calculating the kinetic energy due to translation of the sphere at the given speed.

You mean this ?

Translation:

Ke = (1/2)(m)(v^2)

 

[SteamKing]

Ya. Now reread your problem statement very carefully.