Answer:
A
Explanation
i think its a not 100% sure though.
Answer: 80 Newton
Explanation:
Initial velocity of ball = +20 m/s.
Final velocity of ball = -20 m/s
Mass of ball = 0.1kg
Time taken = 0.05 seconds
Average force = (Change in momentum of moving ball / Time taken)
Since, change in momentum = Mass (final velocity - initial velocity)
Change in momentum =0.1 x (-20 - (+20))
= 0.1 x (-20-20)
= 0.1 x (-40)
= -4.0 kgm/s
Then, put -4.0 kgm/s in the equation of force when Average Force = (Change in momentum / Time taken)
= (-4.0kgm/s / 0.05 seconds)
= 80Newton (note that the negative sign does not reflect on the magnitude of force)
Thus, the average force exerted on the ball is 80N
