ROTATIONAL MOTION

What is the significance of the cross product in torque?

• It makes torque a scalar
• It gives torque both magnitude and direction
• It reduces computation
• It is unnecessary

What is required for mechanical equilibrium of a rigid body?

• Only ƩF = 0
• Only Ʃτ = 0
• Both ƩF = 0 and Ʃτ = 0
• Velocity is zero

What is the kinetic energy of rotation analogous to?

• Potential energy
• Heat energy
• Translational kinetic energy
• Chemical energy

How is rotational equilibrium defined?

• Net external force is zero
• Net external torque is zero
• All forces are zero
• Body is not rotating

What is the condition for conservation of angular momentum?

• Zero external force
• Zero internal force
• Zero external torque
• Constant angular velocity