College Physics 2.21 – Deceleration of a ball caught in a mitt


A well-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?


Solution:

The formula in solving for the initial velocity is

\displaystyle \text{v}_0=\text{v}-\text{at}

Substitute the given values

\displaystyle \text{v}_0=0\:\text{m/s}-\left(-2.10\times 10^4\text{ m/s}^2\right)\left(1.85\times 10^{-3}\:\text{s}\right)

\displaystyle \text{v}_0=38.85\:\text{m/s}