ROTATIONAL MOTION

What is the velocity of the centre of mass if two equal masses move toward each other with equal speeds?

• v
• 2v
• v/2
• Zero

How does the centre of mass concept help in analyzing rigid body motion?

• By eliminating rotation
• By making the body massless
• By separating translational motion from rotational motion
• By reducing size

What is the physical meaning of Eq. (6.10)?

• Only external forces are included
• Internal forces dominate
• The product of total mass and CM acceleration equals the vector sum of all forces on all particles
• The system is in equilibrium

In the absence of external forces, how does the centre of mass move?

• With increasing speed
• With decreasing speed
• With constant velocity
• In a circular path

What is the significance of assuming constant masses in deriving Eq. (6.8)?

• It makes the velocity zero
• It eliminates gravity
• It allows the mass to be factored out during differentiation
• It reduces the number of particles