Answer:
Acceleration will be 1775 [tex]m/sec^2[/tex]
Explanation:
We have given that pitcher throws the ball with speed of 31 m/sec
And the ball bounce back with a speed of 40 m/sec
Time [tex]t=4\times 10^{-2}sec[/tex]
From first equation of motion we know that v = u+at
So acceleration [tex]a=\frac{v-u}{t}=\frac{40-(-31)}{4\times 10^{-2}}=1775m/sec^2[/tex] (for calculation we take -31 because it is in opposite direction )