1. Nov 12, 2008

### jman0391

1. The problem statement, all variables and given/known data

A 6.90 coin is placed 13.0 from the center of a turntable. The coin has static and kinetic coefficients of friction with the turntable surface of = 0.740 and = 0.450.

What is the maximum angular velocity with which the turntable can spin without the coin sliding?

2. Relevant equations
n/a

3. The attempt at a solution
n/a
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

2. Nov 13, 2008

### asleight

$$\sum\vec{F}=m\vec{a}$$

and

$$\vec{a}=\vec{v}^2/r$$.

3. Nov 13, 2008

### LowlyPion

Welcome to PF.

Without knowing what your units are generally you need to figure what point at which the static frictional force will be overcome by the outward force on the coin from rotation. The frictional force depends on the coefficient of friction and its weight which is mass times gravity.