A Ball Bearing Rolls Along a Smooth Horizontal Tabletop and Crashes

question 88

Multiple Choice

A ball bearing rolls along a smooth horizontal tabletop and crashes head-on into a second, stationary ball bearing of half its mass. If both ball bearings roll in the x-direction only (either positive or negative) and the initially stationary ball is observed to have a velocity of +2.4 m/s after the collision, what was the initial speed of the first ball bearing? Assume the collision is elastic.

• A) More information is required
• B) 7.2 m/s
• C) 3.6 m/s
• D) 1.8 m/s

---

Definitions:

Oppositional Defiant Disorder

A childhood disorder characterized by a pattern of disobedient, hostile, and defiant behavior towards authority figures.

Intermittent Explosive Disorder

Intermittent Explosive Disorder is characterized by episodes of sudden, severe anger and aggressive behavior out of proportion to the situation.

Common Treatments

General therapeutic practices or interventions that are widely used to address various medical, psychological, or health conditions.

Antisocial Personality Disorder

A long-standing mental disorder involving a consistent pattern of neglecting or violating others' rights.