The final momentum of the ball is 3.8 kgm/s.
The impulse received by the ball is equal to change in momentum of the ball.
J = ÎP
where;
ÎP = Pâ - Pâ
Pâ = ÎP + Pâ
The final momentum of the ball is calculated as follows;
Pâ = 8 + (- 0.1 x 42)
Pâ = 8 - 4.2
Pâ = 3.8 kgm/s
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