Question

the driver of train A moving at a speed of 30 metre per second sight another train B moving on the same track in same direction at a speed of 10 metre per second it immediately applies break energy is the uniform retardation of 4 metre per second square to avoid head on collision the minimum distance between the trains ?​

Answer 1

The relative speed between the two trains is :

30 - 10 = 20m/s

This is the initial relative speed.

When brakes are applied the train slows down.

Given the acceleration = 4 m/s²

u = 20 m/s

With time the train comes to a sudden stop making the velocity 0.

V² = U² - 2as

0 = 400 - 8s

400 = 8s

S = 400/8

S = 50m