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^_^physicist

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## Homework Statement

A billard ball of radius 'a' is intially spinning about a horizontal axis with angular speed w and with zero forward speed. If mu is the coefficent of sliding friction between the ball and the table, find the distance the ball travels before slipping ceases to occur.

## Homework Equations

Radius of gyration= 2/5*a^2, through the center of mass.

v=r*w

I*w=F(sub p)*r, where I is the moment of inertia, and F(sub p) is the fictional force parallel to the plane.

## The Attempt at a Solution

So far, I have been able to determine that the intial velocity is equal to a*w(sub intial). But this doesn't do me much good.

I am more or less having a hard time trying to set up a force equation to solve.

I was thinking that the equation of motion would look something like this

m*a= (I*w)/a - f, where f (lower case) is the force due to friction).

But I don't think this is right.

Any ideas?