When braking, a passenger train moves with an acceleration of 0.3 m / s2 and stops

When braking, a passenger train moves with an acceleration of 0.3 m / s2 and stops 1 minute after the start of braking. Find the initial speed.

Initial data: a (the acceleration with which the train moves when braking) = -0.3 m / s ^ 2 (a <0, since the movement of the train is slowed down); t (train deceleration time) = 1 min = 60 s; V (train speed after braking) = 0 m / s.

We express the initial train speed (V0) from the following formula: V = V0 + a * t, whence 0 = V0 + a * t and V0 = -a * t.

Let’s calculate: V0 = – (- 0.3) * 60 = 18 m / s.

Answer: The initial speed of the passenger train was 18 m / s.