ROTATIONAL MOTION

How does the center of mass motion differ from the motion of individual particles in a system?

• CM always moves faster
• CM always stops
• Center of mass follows uniform motion if no external force, while individuals may accelerate
• CM moves in circles

In Fig. 6.13(b), why do the radon and alpha particle move back to back?

• To minimize energy
• Because of electric repulsion
• To conserve momentum with zero initial momentum
• Due to magnetic fields

What happens to the center of mass when a moving nucleus decays into two particles?

• It stops suddenly
• It reverses direction
• It accelerates
• It continues along the original path

Why do the trajectories of binary stars appear complicated in the lab frame?

• Due to gravitational waves
• Because of light interference
• They combine orbital motion and center of mass motion
• Stars change speed randomly

In the center of mass frame, what is the net momentum of a two-particle decay system?

• Equal to mc
• Maximum possible
• Zero
• Depends on mass ratio