ROTATIONAL MOTION

How is the total linear momentum of a system related to the centre of mass?

• It is zero always
• It depends only on rotational speed
• It is equal to the total mass times the velocity of the centre of mass
• It is independent of mass

If a rigid body undergoes both translational and rotational motion, how is the translational part described?

• By the motion of its geometric centre
• By the motion of its heaviest part
• By the motion of its centre of mass
• By the angular velocity alone

What is the vector sum of all forces acting on individual particles equal to?

• Zero
• Sum of internal forces
• Sum of external forces only
• Total gravitational force

In a system of particles, what remains unaffected by internal forces?

• Kinetic energy
• Potential energy
• Motion of the centre of mass
• Rotational inertia

What is the role of external forces in the motion of the centre of mass?

• They create internal energy
• They balance internal forces
• They determine the acceleration of the centre of mass
• They cause deformation