ROTATIONAL MOTION

Why can a body have angular momentum without orbiting a point?

• It cannot
• Because gravity pulls it
• Because any linear motion with a moment arm relative to a point contributes to angular momentum
• Because time is curved

How does the choice of origin affect torque calculations when net force is not zero?

• It has no effect
• Torque becomes zero
• Torque value depends on the origin
• It doubles the force

What is the main difference between torque and force in rigid body dynamics?

• They are the same
• Force is scalar
• Force changes linear momentum, torque changes angular momentum
• Torque affects mass

Why is the conservation of angular momentum important in figure skating?

• It helps them jump
• It reduces weight
• Skaters change their moment of inertia to control spin speed
• It keeps them warm

What happens to a rigid body if it satisfies translational equilibrium but not rotational?

• It stops moving
• It vanishes
• It may rotate with increasing angular speed
• It becomes liquid