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Two friends on roller-skates are standin...

Two friends on roller-skates are standing `5m` apart facing eachother. One of them throws a ball of `2kg` towards the other, who catches it. How will this activity affect the position of the two? Explain your answer.

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In the process, sepration between the two friends on roller skates will increase. To start with. Both, are at rest. When one throws the ball, he aquires a momentum (equal to momentum of the ball) in opposite direction and moves in opposite direction. The other friend who catches the ball acquires the momentum of the ball and moves away from his friends in the direction of motion of the ball.
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