A 4.80 g coin is placed 11.0 cm from the center of a turntable. The coin has static and kinetic coefficients of friction with the turntable surface of us = 0.770 and uk = 0.400.
What is the maximum angular velocity with which the turntable can spin without the coin sliding? (In rad/s)
Ff = FN(u)
Fa = (mv^2)/r
The Attempt at a Solution
I've always been a little foggy on rotational motion, but for this I converted the grams to kilograms and the centimeters to meters, then set the friction equal to the acceleration:
(.0048)(9.8)(.77) = [(.0048)(v^2)]/.11
Which gave me a v of .911 rad/s. I'm not sure what I did wrong/what I'm missing.