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WahooMan
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Homework Statement
A block of mass 3.5kg rests on a rough horizontal turntable at a distance of 1.2m from the axis of rotation. If the block begins to slide when the turntable is rotating at 20.0 rev/min, what is the coefficient of static friction between the block and the turntable?
Homework Equations
Fg = -mg
Fn = mg
Ff = Fn(mu)
radial acceleration (aR) = v^2/r
The Attempt at a Solution
Fg = -mg = -9.80(3.5) = -34.3N
Fn = mg = 34.3N
c = 2pi(r) = 2pi(1.2) = 7.54m
v = 7.54m*20 = 150.8m/60s = 2.51m/s
aR = 2.51^2/1.2 = 5.26m/s^2
Now I think I am supposed to use sum of the forces = ma, but I'm not sure if there is a force acting on the mass pushing it to the outside of the turntable (I'm pretty sure there is, but I don't know how to calculate it.)