After the jolt, the car with a mass of 20 tons stopped after 50 seconds, having covered a distance of 125 m.

After the jolt, the car with a mass of 20 tons stopped after 50 seconds, having covered a distance of 125 m. Determine the braking force.

Data: m (wagon weight) = 20 t (in SI m = 20 * 10 ^ 3 kg); t (duration of the movement of the car after the push) = 50 s; S (distance traveled) = 125 m.

1) Determine the speed of the car after the push: S = (V + V0) * t / 2 = (0 + V0) * t / 2, whence V0 = 2S / t = 2 * 125/50 = 5 m / s.

2) Let’s calculate the acceleration: V = 0 = V0 – a * t, whence a = V0 / t = 5/50 = 0.1 m / s2.

3) Let’s define the braking force: Fstorm. = m * a = 20 * 10 ^ 3 * 0.1 = 2 * 10 ^ 3 N (2 kN).

Answer: The braking force was 2 kN.