Exam-style question
Try this first
Which of the following best describes the relationship between the work done on a rotating object and its change in rotational kinetic energy?.
- A.The work done equals the increase in the object's rotational kinetic energy.
- B.The work done equals the decrease in the object's rotational kinetic energy.
- C.The work done is unrelated to the object's rotational kinetic energy.
- D.The work done equals the sum of the object's rotational kinetic energy and its potential energy.
Model answer
What a good answer should say
- The work done equals the increase in the object's rotational kinetic energy.
Explanation
Why this works
The work–energy theorem for rotation states that the net work done by all torques on a rigid body equals the change in its rotational kinetic energy. This directly links work and rotational energy conservation.
Common mistake
No common mistake is linked to this question yet.