Your friend works in a bookstore where lab books for science are assembled . Each lab book uses 2 covers, 50 sheets of lined paper, 25 sheets of graph paper and 3 staples. Her inventory includes 150 covers, 7500 sheets of lined paper and 3000 sheets of graph paper and 250 staples. What is the "limiting reactant?" How many complete lab books can be made? How much of each of the other reactants remain in excess?

(newtons first law)

conservation of momentum law states :

momentum before collision = momentum after collision

momentum p (kg-m/s)= mass * velocity

say moving car=1 000 kg, velocity = 10 m/s then p = 1 000*10= 10 000 kg-m/s

say still car = 2 000 kg, velocity = 0 m/s then p = 2 000* 0 = 0 kg-m/s

total momentum prior to collision = 10 000 + 0 = 10 000 kg-m/s

momentum after collision = 10 000 kg-m/s

mass now = 1 000 kg+2 000 kg = 3 000 kg

10 000 = 3 000 kg* velocity m/s

10 000/3 000 = velocity

3.33 m/s = velocity after collision

an impulse is a force applied over time , momentum is exclusive of external forces and a perfect collision is implied