A 2.00-kg sphere is rotating about an axis through its center at 40.0 rev/s with the angular velocity in the +z direction. A torque 10.0 Nm acts on the sphere about the center of the sphere in the +x direction. What is the rate of change of the angular momentum of the sphere?

Question

A 2.00-kg sphere is rotating about an axis through its center at 40.0 rev/s with the angular velocity in the +z direction.  A torque 10.0 Nm acts on the sphere about the center of the sphere in the +x direction.  What is the rate of change of the angular momentum of the sphere?
A. -20.0 kg m2/s2.
B. 20.0 kg m2/s2.
C. 80.0 kg m2/s2.
D. 8.00 kg m2/s2.
E. 10.0 kg m2/s2.

toby · Answer

Rate of change of angular momentum" is a synonym for "torque." Most of the numbers given in the problem are irrelevant.