A train with a mass of 2000 tons, moving in a straight line, reduced the speed from

A train with a mass of 2000 tons, moving in a straight line, reduced the speed from 54 to 36 km / h. What is the change in the impulse of the train?

Given:

m = 2000 tons = 2,000,000 kilograms – train weight;

v1 = 54 km / h = 15 m / s – the initial speed of the train;

v2 = 36 km / h = 10 m / s – the final speed of the train.

It is required to determine dP (kg * m / s) – the change in the impulse of the train.

dP = P2 – P1 = m * v2 – m * v1 = m * (v2 – v1) =

= 2,000,000 * (10 – 15) = 2,000,000 * (-5) = -10,000,000 kg * m / s =

-10 ^ 7 kg * m / s.

Answer: the change in momentum is -10 ^ 7 kg * m / s.