Question

Which of the following statements is incorrect?

• A. A fan is rotating about a fixed axis then net torque on the fan may be zero.
• B. Moment of inertia of particle about an axis depends on perpendicular distance from the axis.
• C. For equilibrium of a rigid body net force & net torque must be zero.
• D. For a large cubical box sliding down a rough inclined plane normal force on box must pass through center.

Answer 1

The correct option is D For a large cubical box sliding down a rough inclined plane normal force on box must pass through center.

N does not necessarily pass through center and can shift to provide counter torque to oppose rolling of body due to moment of friction.