2. A 1200kg car slows down using an average braking force of 1400N over a time interval of 10s. If the distance it travels while slowing down is 120m:

(a) What impulse does the car experience?

(b) What is the car's acceleration?

(c) How much work has been done on the car?

(d) How much power is used in stopping the car?

4. A 0.14 kg baseball is pitched at a speed of 35 m/s. If it is hit straight back at the pitcher with a force of 5400N exerted over a time interval of 1.0 millisecond, find:

(a) the acceleration of the baseball (hint, use a = F/m)

(b) the impulse given to the baseball (hint, use J = Ft)

(c) the change in momentum of the baseball (hint, p = J)

(d) the initial momentum of the baseball (hint, p_i = mv)

(e) the final momentum of the baseball (hint, p_f - p_i = p, so p_f = p + p_i

(f) the final velocity of the baseball (hint, use v_f = ^p_f / _m)

(g) the distance that the baseball was in contact with the bat (hint, use d = v_avet)