The electric train, departing from the stop, increases its speed to 72 km / h in 20 seconds.

The electric train, departing from the stop, increases its speed to 72 km / h in 20 seconds. What is the acceleration of the electric train and what distance did it travel during this time?

Data: V0 (initial speed of the electric train) = 0 m / s (the electric train departed from the stop); V (the speed that the electric train developed) = 72 km / h (20 m / s); t (acceleration duration) = 20 s.

1) Acceleration of the electric train: a = (V – V0) / t = V / t = 20/20 = 1 m / s2.

2) The distance traveled by the electric train: S = (V ^ 2 – V0 ^ 2) / 2a = V ^ 2 / 2a = 20 ^ 2 / (2 * 1) = 200 m or S = V0 * t + 0.5 * a * t ^ 2 = 0.5 * a * t ^ 2 = 0.5 * 1 * 20 ^ 2 = 200 m.

Answer: The electric train was moving with an acceleration of 1 m / s2 and managed to cover the distance of 200 m.