A train weighing 500 tons, moving at an equal slowdown for 1 minute

A train weighing 500 tons, moving at an equal slowdown for 1 minute, decreases its speed from 40 to 28 km / h. Find the force acting on the train.

Initial data: m (train mass) = 500 t (in SI m = 500 * 10 ^ 3 kg); t (duration of movement) = 1 min (in SI t = 60 s); Vн (initial train speed) = 40 km / h (in SI Vн = 11.11 m / s); Vk (final speed) = 28 km / h (in SI Vk = 7.78 m / s).

To calculate the force acting on a given train for 1 minute, we use Newton’s second law: F = m * a = m * (Vn ^ 2 – Vk ^ 2) / t.

Calculation: F = 500 * 10 ^ 3 * (11.11 ^ 2 – 7.78 ^ 2) / 60 = 27.8 * 103 N (27.8 kN).

Answer: The effective force was 27.8 kN.