Trains problem are depends on the concept of time, distance and speed.

Speed in km/hr

Speed in m/s

Time taken by a train of length L metres to pass a pole or a standing man or a signal post is equal to the time taken by the train to cover

Time taken by a train of length L metres to pass a stationary object of length b metres is the time taken by the train to cover

Suppose two train or two bodies are moving in the same direction at u m/s and v m/s , where u > v, then their

Suppose two trains or two bodies are moving in opposite directions at u m/s and v m/s , then their

If two trains of length a metres and b metres are moving in opposite directions at u m/s and v m/s, then time taken by the trains to cross each other

If two train s of length a metres and b metres are moving in the same direction at u m/s and v m/s , then the time taken by the faster train to cross the slower train

If two train ( or bodies) start at the same time from points A and B towards each other and after crossing they take a and b sec in reaching B and A respectively, then

a km /hr =

a * 5
18

m/s.
a m/s =

a * 18
5

km/hr.
L Metres.

(L + b) metres.

relative speed = (u - v) m/s.

relative speed = ( u + v) m/s.

(a+b)
( u+ v)

sec.
(a+b)
( u+ v)

sec.
( A speed) : ( B speed) = ( vb : va ).