Question

at a baseball game a ball of mass m = 0.15 kg moving at a speed v = 40 m/s is caught by a fan. part a find that the impulse supplied to bring the ball to rest. express your answer to two significant figures and include the appropriate units. j = value units

Explanation:

Step1: Recall impulse - momentum theorem

The impulse $J$ is equal to the change in momentum $\Delta p$. The formula for momentum is $p = mv$. The initial momentum $p_i=mv$ and the final momentum $p_f = 0$ (since the ball comes to rest). So, $J=\Delta p=p_f - p_i$.

Step2: Calculate initial momentum

Given $m = 0.15\ kg$ and $v = 40\ m/s$. The initial momentum $p_i=mv=0.15\times40\ kg\cdot m/s = 6.0\ kg\cdot m/s$. The final momentum $p_f = 0$. Then $J=p_f - p_i=0 - 6.0\ kg\cdot m/s=- 6.0\ kg\cdot m/s$. The magnitude of the impulse is $6.0\ kg\cdot m/s$.

Answer:

$J = 6.0\ kg\cdot m/s$