Ball #1 slides down from rest along a smooth parabolic curve y=x^2/5. It will hit ball #2 at the bottom and ball #2 will possibly hit ball #3, and then ball #4 and so on, like a relay. Assume that all balls are modeled as identical particles of mass m=0.2kg. Balls 2,3 ... are initially placed at rest along the x-axis, 5m apart. Also, assume that the horizontal path is rough and the kinetic friction coefficient ?k during the motion is 0.2. The coefficient of restitution e=0.8. Take g=10m/s/s.

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