## Work and Power for Rotational Motion

10.8 Work and Power for Rotational Motion

### Learning Objectives

By the end of this section, you will be able to:

- Use the work-energy theorem to analyze rotation to find the work done on a system when it is rotated about a fixed axis for a finite angular displacement
- Solve for the angular velocity of a rotating rigid body using the work-energy theorem
- Find the power delivered to a rotating rigid body given the applied torque and angular velocity
- Summarize the rotational variables and equations and relate them to their translational counterparts

**Discuss!**

Consider how you would answer these questions. Then bring this to class for a group discussion.

A rope pulls on a spool with a constant force, causing it to rotate. As the spool rotates, the rope rolls off. (The distance r changes as the rope comes off the spool.) How much work is done during the first rotation of the spool?