ROTATIONAL MOTION

What is the main difference between elastic and inelastic collisions in terms of center of mass motion?

• Only elastic collisions preserve it
• Only inelastic collisions change it
• It changes in both
• The center of mass velocity remains unchanged in both cases

Why can't a single force produce pure rotation in a free rigid body?

• Forces cannot cause rotation
• Rotation requires no force
• Only gravity can rotate bodies
• It would also cause translational motion

What is the role of static friction in pure rolling motion?

• It slows down the object
• It increases kinetic energy
• It causes slipping
• It prevents slipping at the point of contact

What determines whether a body will topple when tilted?

• Its temperature
• Its color
• Its linear speed
• Position of the center of mass relative to the base of support

How is the kinetic energy of a rolling object expressed?

• Only as (1/2)mv²
• Only as (1/2)Iω²
• As (1/2)mvω
• As the sum of translational and rotational kinetic energies