Answer to Question #138927 in Classical Mechanics for dein

Question

Which of the following statements is the one that is correct?
A. If all the forces on a body act through the axis of rotation, the angular acceleration will be zero.
B. If two bodies have the same moment of inertia about their centers of mass and the same mass, they must be identical.
C. Two disks roll down an inclined plane without slipping. The one with a smaller radius will always reach the bottom first independent of their masses.
D. Two disks roll down an inclined plane without slipping. The one with a bigger radius will always reach the bottom first independent of their masses.
E. Two disks roll down an inclined plane without slipping. The one with a bigger mass will always reach the bottom first.

Answer 1

The net torque will be zero.

Answer: A. If all the forces on a body act through the axis of rotation, the angular acceleration will be zero.