The train moves along the straight track at the speed of V = 54km / h. for some reason, it needs to stop for 1min at a small station. The acceleration of the train when braking at the station

The train moves along the straight track at the speed of V = 54km / h. for some reason, it needs to stop for 1min at a small station. The acceleration of the train when braking at the station

The braking time t is not t0
Initial velocity V, final velocity VT = 0
Acceleration a = (final velocity initial velocity) / T
The condition here is insufficient, and the acceleration is an indefinite value

A passenger is sitting at the window of a train with a speed of 54 km / h. a train is coming towards him with a speed of 36 km / h
A passenger is sitting at the window of a train with a speed of 54km / h, and a train is coming. Its speed is 36km / h, and its length is 150m. How long does it take for the passenger to see the train running along his side?

150m = 0.15 km
So it takes 0.15 △ 54 + 36 = 1 / 600 hours
1/600×3600=6
So it takes six seconds

When the train running at 36km / h starts to go downhill, the acceleration on the slope is equal to 0.2m/s2, and reaches the bottom of the slope after 30s. The length of the slope and the speed when the train reaches the bottom of the slope are calculated

According to the displacement formula, x = v0t + 12at2 = 10 × 30 + 12 × 0.2 × 302M = 390m; according to the speed formula, v = V0 + at = 10 + 0.2 × 30m / S = 16m / s

When the train starts to go downhill at the speed of 10 meters per second, the acceleration on the slope is equal to 0.2 meters per second, and the speed at the bottom of the slope is 16 meters per second, so the speed of the slope can be calculated

V end = V beginning + at
V = 16 m / S
V = 10 m / S
a = 0.2 m^2/s
It can be concluded that t = (V end-v beginning) △ a = (16-10) △ 0.2 = 30 s
Then the slope length is s = (V beginning + V end) * t / 2 = 390 M