Physics-
General
Easy
Question
If an ivory ball of mass 2 m moving with a velocity ' 
' strikes head on to a close row of three identical ivory balls each of mass m as shown in the figure. Then after the collisions which may be assumed as elastic, which of the following would occur?
- The balls numbered 2 and 3 will move with velocity v, the others staying at rest.
- The ball numbered 3 will move with velocity 2v, all others staying at rest.
- The ball numbered 3 moves with velocity 4v/3 and the striking ball moves with velocity v/3
- The balls numbered 1, 2 and 3 move with velocity v/3 and the striking ball stops dead.
The correct answer is: The ball numbered 3 moves with velocity 4v/3 and the striking ball moves with velocity v/3
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