Question

If a cricket ball moves with a velocity ‘v’ and collides with a tiny table tennis ball. After an elastic collision, at what velocity will the second ball move?

(a) v

(b) v/2

(c) 2v

(d) v^2

The question was posed to me during an interview for a job.

Enquiry is from Kinetic Energy Correction and Momentum Correction Factors topic in section Viscous Flow & Turbulent Flow of Fluid Mechanics

Answer 1

The correct choice is (c) 2v

Explanation: Since the collision is elastic, the cricket ball having a higher mass than that of the tiny table tennis ball will hit and generate a higher velocity. After immediate impact, the table tennis ball will move exactly with twice the velocity of the cricket ball.