Question

1....How much force needed to bring a 3200 lb car from rest to a velocity of 44 m/s in 8 sec.?
2....A ball with a mass of 2 kg move to the right with a speed of 2 m/s. It hits a ball of mass 0.50 kg which is at rest. After collision the second ball moves to the right with a speed of 1 m/s. What happens to the first ball?...Suppose that the 2 balls stick together moves as one after collision, what is their final velocity?

Answer 1

1. Force*time=changemomentum

2. Momentum is conserved.

Answer 2

1. Impulse = force x time
= momentum change

Apply the formula

2. Total momentum remains the same.

In the second case,
M1* (2 m/s) = (M1 + M2)*Vfinal
Vfinal = (2/2.5)* 2 m/s = __

Try doing the first case yourself. Make sure + is right and - is left for velocity.