﻿ The driver of a train A moving at a speed of 30 ms–1 sights another trainB moving on the same track at a speed of 10 ms–1 in the same direction. He immediately applies brakes and achieves a uniform retardation of 2 ms–1. To avoid collision, what must be the minimum distance between the trains?       : Kaysons Education

# The Driver Of A Train A moving At A Speed Of 30 Ms–1 sights Another TrainB moving On The Same Track At A Speed Of 10 Ms–1 in The Same Direction. He Immediately Applies Brakes And Achieves A Uniform Retardation Of 2 Ms–1. To Avoid Collision, What Must Be The Minimum Distance Between The Trains?

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## Question

### Solution

Correct option is

100 m

The relative speed of train A with respect to train B = 30 – 10 = 20 ms–1. To avoid collision, let the minimum distance between them be s. this means that the relative speed must reduce to zero when the distance covered is s. Using  we have

Which gives s = 100 m.

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