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

Calculate the work done on a solid cylinder of mass 5.0 kg and radius 55.6 cm by an applied force of 12.2N if it turns 45 degrees.

**2. Relevant equations**

W = torque x angle (radians)

**3. The attempt at a solution**

I just used:

W = torque x angle

= Force x perpendicular radius x angle

= 12.2 x 55.6 x pi/4

Why is this wrong? I think it’s wrong, because part b of the question asks how the answer would change if the object was a ring.

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