ROTATIONAL MOTION

How does the centre of mass move under uniform gravitational field?

• With increasing acceleration
• With decreasing acceleration
• With constant acceleration
• In a straight line

What is the main advantage of using the centre of mass frame?

• All particles are at rest
• Kinetic energy is zero
• The total momentum is zero in this frame
• It is always inertial

If a system explodes due to internal forces, what happens to the centre of mass?

• It stops suddenly
• It accelerates
• It continues with the same velocity
• It moves randomly

What is the time derivative of the total momentum of a system equal to?

• Zero
• Internal force sum
• Net external force
• Kinetic energy

What is the unit of the position vector of the centre of mass?

• Kilogram (kg)
• Meter per second (m/s)
• Newton (N)
• Meter (m)