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a) The change in momentum of the ball.
Note that the ball is initially at rest, i.e. u=0m/s.
?P=mv-mu=(0.65*15)-(0.65*0)=9.75kgm/s
b) The average force exerted on the ball.
F=m(v-u)/t =(9.75kgm/s)/0.03s)=325N
c) The displacement of the ball in 2 seconds.
The upward acceleration of the ball is negative 2m/s5.
Moraa orina answered the question on April 8, 2018 at 17:35
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