# Radians and Angular Motion

1. Oct 5, 2009

### Unity

1. The problem statement, all variables and given/known data
When a wheel is rotated through an angle of 35o, a point on the circumference travels through an arc length of 2.5m. When the wheel is rotated through angles of 35 radians and 35 revolutions, the same point travels through arc lengths of 143m and 9.0 x 102m, respectively. What is the radius of the wheel?

DeltaS = 2.5m
DeltaTheta = 35o
r = ?

2. Relevant equations
r = DeltaS / Delta Theta

3. The attempt at a solution
Okay, so first i converted 35o to radians and came out with .61 radians.
(35o x Pie) / 180o = .61 radians

Next I plugged the variables into the equation.
2.5m / .61 radians = 4.1m. Thus 4.1 being the radius.
My main concern is the other information that i was given, is it relevant to the problem? Or is it simply extra information?

2. Oct 5, 2009

### rl.bhat

Hi Unity, welcome to PF.
As you have said, the first information is sufficient to find the radius.

3. Oct 5, 2009

### Unity

Thanks for the answer man. I'll definantly be sticking around.