Question

A(n) 0.212 kg baseball is thrown with a speed of 18.8 m/s. It is hit straight back at the pitcher with a final speed of 21.2 m/s. What is the magnitude of the impulse delivered to the ball?

Answer 1

Answer:

Impulse will be 8.4788 kgm/sec

Explanation:

We have given mass of the ball m = 0.212 kg

Initial velocity u = 18.8 m/sec

We know that momentum P = mass×velocity

Taking initial velocity as negative

So initial momentum = 0.212×-18.8 = -3.9856 kgm/sec

Final velocity is given as v = 21.2 m/sec

So final momentum = 0.212×21.2 = 4.4944 kgm/sec

We know that impulse is given by change in momentum

So impulse = final momentum-initial momentum = 4.4944-(-3.9844 ) = 8.4788 kgm/sec