Question

A well-thrown ball is caught in a well-padded mitt. If the deceleration of the ball is 2.10\times 10^{4} m/s^2, and 1.85 ms \left(1\:ms=10^{-3}\:s\right) elapses from the time the ball first touches the mitt until it stops, what was the initial velocity of the ball?

Answer 1

Answer:

38.85 m/s

Explanation:

a = Acceleration = $-2.10\times 10^{4}\ m/s^2$ (negative sign due to deceleration)

t = Time taken = 1.85 ms

u = Initial velocity

v = Final velocity = 0

Equation of motion

$v=u+at\\\Rightarrow v-at=u\\\Rightarrow u=0-1.85\times 10^{-3}\times -2.10\times 10^{4}\\\Rightarrow u=38.85\ m/s$

Initial velocity of the ball is 38.85 m/s