ROTATIONAL MOTION

What is the momentum of a system of two identical particles moving in opposite directions with the same speed?

• Twice the momentum of one particle
• Equal to one particle's momentum
• Half the momentum of one particle
• Zero

Under what condition does the center of mass of a system accelerate?

• Whenever internal forces act
• When particles move randomly
• When the system rotates
• When a net external force acts on the system

What is the effect of a sudden internal explosion on the kinetic energy of a system?

• It always decreases
• It remains unchanged
• It becomes zero
• It can increase due to conversion of internal energy

How does the velocity of the center of mass relate to the individual velocities of particles in a system?

• It is the arithmetic average of all velocities
• It is always zero
• It is the highest individual velocity
• It is the mass-weighted average of all particle velocities

What is the main advantage of using the center of mass concept in physics?

• It eliminates all forces
• It makes calculations longer
• It increases complexity
• It simplifies the analysis of complex systems