# Centripetal Force with angle problem

## Homework Statement

Consider the figure below, a ball of mass m=0.100 kg tied by a string of 0.100 m travels in a circular motion with 2 revolutions per second. Find the angle θ that keeps the ball stationary.
Given: m = 0.100 kg, v = 2 rev/sec L = 0.100 m (radius?)
[PLAIN]http://img192.imageshack.us/img192/9518/unledrht.jpg [Broken]

## Homework Equations

FC = $\frac{mv^{2}}{r}$

## The Attempt at a Solution

Let T be the tension force.
y: Tcosθ - mg = 0
x: Tsinθ = mv2/r

The problem is I am not sure if the setup above is right, and should I take the length of the string as the radius? or rsinθ?
Hope you guys can help me, thank you very much, I will be extremely appreciated!!

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