A 1500 kg car traveling at 30 m/s hits a stationary 1200 kg car. If they stick together on collision, what is the final velocity of the two cars?

16.67 m/s

Explanation:

Let that velocity be v.

Using conservation of momentum:

Initial momentum = final momentum

momentum of car1 = momentum of cars

mass1 x velocity1 = (m1 + m2)v

1500*30 = (1500 + 1200)v

45000/2700 = v

16.67 m/s = v

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