Answer:
(a)
(b)
1120 N
Explanation:
Change in velocity, is given by subtracting the initial velocity from the final velocity and expressed as
Where v represent the velocity and subscripts f and i represent final and initial respectively. Since the ball finally comes to rest, its final velocity is zero. Substituting 0 for final velocity and the given figure of 8 m/s for initial velocity then the change in velocity is given by
To find then we substitute 7 kg for m and -8 m/s for
therefore
(b)
The impact force, F is given as the product of mass and acceleration. Here, acceleration is given by dividing the change in velocity by time ie
Substituting t with 0.05 s then
Since F=ma then substituting m with 7 Kg we get that F=7*-160=-1120 N
Therefore, the impact force is equivalent to 1120 N