Two trains(both are 400m in lenght) are travelling on two parallel tracks with the same speed 72kmph.train A is ahead of train B. Now train B driver decides to overtake train A and accelarates at 1m/s²

and manages to overtake in 50 sec.Now calculate the initial seperation between the trains before the train B's accelaration?

Dear karthik

let the initial seperation = x

In train A frame of reference .velocity of train A is zero.initia velocity of train B is zero.

to overtake train A ,train A has to cover L+800 distance.

so

 S =1/2at²

L+800 =1/2 *1 * (50)²

L=450 m

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