1. Conservation of Momentum

2. The law of conservation of momentum states that total momentum remains constant (When we ignore friction).

4. 1. An object separates into pieces:
3 Possible situations:
1. An object separates into pieces:
MiVi= Mf1Vf1 + Mf2Vf2
2. Two objects collide and stick together:
Mi1Vi1 + Mi2Vi2 = Mf(1+2)Vf
3. Two objects collide and separate:
Mi1Vi1 + Mi2Vi2 = Mf1Vf1 + Mf2Vf2

5. A 600 kg ship is traveling at 1000 m/s
A 600 kg ship is traveling at 1000 m/s. The ship burns off 100 kg of fuel and the fuel is propelled out of the back of the ship at 2000 m/s. What is the final speed of the ship after the fuel is expelled? *Remember to consider direction!

6. Mi(r +f)Vi(r + f) = Mf(r)Vf(r) +Mf(f)Vf(f)
A 600 kg ship is traveling at 1000 m/s. The ship burns off 100 kg of fuel and the fuel is propelled out of the ship at 2000 m/s. What is the final speed of the ship after the fuel is expelled?
Mi(r +f)Vi(r + f) = Mf(r)Vf(r) +Mf(f)Vf(f)
( )(1000) = 600(Vf(r) ) + 100(-2000)
700,000 = 600(Vf ) - 200,000
700, ,000 = 600(Vfr )
900,000 = 600Vf Vf = 1,500 m/s

7. A 2,000 kg truck traveling at 30 m/s North collides into a 1,000 kg car travelling at 10 m/s South. The vehicles stick together after the collision. What is their final velocity? Be sure to include direction!

8. Mi(t)Vi(t) + Mi(c)Vi(c) = Mf(t+c)Vf
A 2,000 kg truck traveling at 30 m/s North collides into a 1,000 kg car travelling at 10 m/s South. The vehicles stick together after the collision. What is their final velocity? Be sure to include direction!
Mi(t)Vi(t) + Mi(c)Vi(c) = Mf(t+c)Vf
(2,000)(30) + (1,000)(-10) = (3,000)Vf
60, ,000 = (3,000)Vf
50,000 = (3,000)Vf
50,000/3,000 = Vf
Vf = m/s North

9. Two pool balls collide. Each ball weights 0. 5 kg
Two pool balls collide. Each ball weights 0.5 kg. One ball has an initial velocity of 7 m/s, while the other ball travels with an initial velocity of 5 m/s. After the collision the first ball travels at 6 m/s. What is the final velocity of the second ball?

10. Two pool balls collide. Each ball weights 0. 5 kg
Two pool balls collide. Each ball weights 0.5 kg. One ball has an initial velocity of 7 m/s, while the other ball travels with an initial velocity of 5 m/s. After the collision the first ball travels at 6 m/s. What is the final velocity of the second ball?
Mi1Vi1 + Mi2Vi2 = Mf1Vf1 +Mf2Vf2
(.5)(7)+ (.5)(-5) = (.5)(6) + (.5)(Vf2)
= 3 + (.5)(Vf2)
1 = 3 + (.5)(Vf2)
-2 = (.5)(Vf2) Vf2 = - 4 m/s