Physics-
General
Easy
Question
Six identical balls are linked in a straight groove made on a horizontal frictionless surface as shown. Two similar balls each moving with a velocity 
collide elastically with the row of 6 balls from left. What will happen
- One ball from the right rolls out with a speed
and the remaining balls will remain at rest
- Two balls from the right roll out with speed each and the remaining balls will remain stationary
- All the six balls in the row will roll out with speed
each and the two colliding balls will come to rest
- The colliding balls will come to rest and no ball rolls out from right
and the remaining balls will remain at rest
each and the remaining balls will remain stationary
each and the two colliding balls will come to rest
The correct answer is: Two balls from the right roll out with speed each and the remaining balls will remain stationary
Momentum and kinetic energy is conserved only in this case
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