Chapter 8, Problem 2Q

To determine

To analyze:

The given situations when a disk rotates at constant angular velocity.

Answer to Problem 2Q

Solution:

a)  A point on the rim has radial acceleration when a disk rotates at constant angular

velocity.

b)  A point on the rim has radial and tangential acceleration when there is uniform

increase in the disk’s angular velocity.

c)  When there is uniform increase in the angular velocity there would be change in the

magnitude of the linear acceleration.

Explanation of Solution

a)  When rotating with constant angular velocity, the direction of the velocity of a point on the rim is changing. Therefore, it has radial acceleration. But, with constant angular speed, the linear speed is constant, and hence there is no tangential acceleration.

b)  If the angular velocity increases uniformly, the point will have both radial and tangential acceleration.

c)  The radial component of acceleration will increase with a uniformly increasing velocity, while the tangential component will be constant. For a uniformly increasing

angular velocity, neither component of linear acceleration will change.