ROTATIONAL MOTION Quiz

• Net external force is zero
• All torques are internal
• Net external torque is zero
• The body is spherical

• It makes L parallel to motion
• It reduces magnitude
• It ensures L is perpendicular to the plane of motion
• It converts to energy

• They repel each other
• They emit light to conserve L
• Their mutual gravitational force is internal and central, so L is conserved
• Internal friction removes angular momentum

• Torque halves
• Torque unchanged
• Torque quadruples
• Torque doubles

• They are always equal
• L is zero at COM
• L can be split into orbital and spin parts relative to COM
• COM has no angular momentum