How Far Can a Bug Crawl on a Spinning CD Before Slipping?

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Warpedintellect
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Homework Statement


A bug crawls outward from the center of a CD spinning at 200 revolutions per min. The static friction coefficient is 1.2 between the bug and cd. How far does the bug get from the center before slipping? https://www.physicsforums.com/Nexus/editor/menupop.gif
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Homework Equations


a = ((2*pi)/T)^2*r //where T is number of seconds it takes to complete a revolution.
f <= "mu"*N // static equation.


The Attempt at a Solution


I started out by trying to find f by using "mu" * g and then trying to solve for r when i have f. So that f = "mu"*a , where a = ((2*pi)/T)^2*r. I don't know if I am even on the right track.
 
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Centrifugal force experienced by the bug when it is at a distance r fron the centre =
m(2*pi)/T)^2*r ( m = mass of the bug).[This force increases as r increases]

Friction force acting on the bug = mu*mg [This force remains constant]

Equate the above two (m gets canceled out) and solve for r. You are on the right track.