A wheel with a 0.10-m radius is rotating at 35 rev/s. It then slows uniformly to 15 rev/s over a 3.0-s interval. What is the angular acceleration of a point on the wheel? A)-2.0 rev/s² B)0.67 rev/s² C)-6.7 rev/s² D)42 rev/s² E)-17 rev/s²

Question

Quizplus · Accepted Answer

We can use the formula for angular acceleration:

angular acceleration = (change in angular velocity) / time

The change in angular velocity is:

final angular velocity - initial angular velocity 
= 15 rev/s - 35 rev/s 
= -20 rev/s

The time is given as 3.0 s.

So, the angular acceleration is:

angular acceleration = (-20 rev/s) / (3.0 s) 
= -6.7 rev/s^2

Note that the negative sign indicates a decrease in angular velocity, which is consistent with the wheel slowing down. Therefore, the best choice is (C).

A Wheel with a 0