Awell-thrown ball is caught in a well-padded mitt. if the deceleration of the ball is 2.10×104 m/s2 , and 1.85 ms (1 ms = 10−3 s) elapses from the time the ball first touches the mitt until it stops, what was the initial velocity of the ball?

u = - 38.85 m/s^-1

Explanation:

given data:

acceleration = 2.10*10^4 m/s^2

time = 1.85*10^{-3} s

final velocity = 0 m/s

from equation of motion we have following relation

v = u +at

0 =  u + 2.10*10^4 *1.85*10^{-3}

0 = u + (21 *1.85)

0 = u + 38.85

u = - 38.85 m/s^-1

negative sign indicate that the ball bounce in opposite directon

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