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?

To calculate the desired change in the impulse of the train under consideration, we apply the formula: ΔР = Рк – Рн = m * Vк – m * Vн = m * (Vк – Vн), where m is the mass of the train (m = 2000 t; in SI m = 2 * 10 ^ 6 kg); Vк – final speed (Vк = 36 km / h; in SI Vк = 10 m / s); Vн – initial speed (Vн = 54 km / h; in SI Vн = 15 m / s).

Let’s calculate: ΔР = 2 * 10 ^ 6 * (10 – 15) = -1 * 10 ^ 7 kg * m / s.

Answer: The sought impulse of the train in question has decreased by 1 * 107 kg * m / s.