Which reaction would cause a decrease in entropy? A. CO(g) + 3H2(g) → CH4(g) + H2009) B. 2NH3(9) ► N2(g) + 3H2(9) O C. 2NOCI(9) + 2NO(g) + Cl2(9) D. 2CC14(9) + O2(g) → 2C0C12(9) + 2Cl2(9)​

(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