Problems on Train:

• How to convert  “x km/hr” into m/s is
x km/hr = x*5/18 m/s
• how to convert  “x m/s” into km/hr is
x m/s = x*18/5 km/hr
•  Two trains in the Same direction (one train with x km/hr speed, second train with y km/hr speed) then total                                    speed = (x+y) km/hr
• Two trains in the opposite direction (one train with x km/hr speed, second train with y km/hr speed) then total speed = (x-y) km/hr
Speed = Distance/time

1.Single Train problems questions:
A train which is 200mlong is running at the speed of 60 km/hr. Find the time taken to pass a man standing at the railway station?
A) In the above train problems, you didn’t think about  man at the railway station, train passes him all those nonsense.
Train length is always Distance, So d= 200m
Speed s = 60 Km/hr
Here Distance is in meters and speed in Km/hr , so you can convert Speed in to m/s
Speed s = 60 Km/hr = (60*5/18) m/s = 50/3 m/s
Now in the question what they ask means just Time?
Time t = d/s = 200/(50/3)= 200*3/50 = 12 sec.

2. Single train + Platform problems questions:
When a train is moving with a speed of 66 km/hr .If the length of train is 55 meters.  How much time it takes to cross a 100 meters platform
Here one thing you remember, in any train problems question they can mention platform length then train length + platform length can b calculated as distance.
So distance d  = (100+55) m = 155 m
Speed s = 66*(5/18) = 110/6 m
As now we know the formulae for time t = d/s = 155/(110/6) = 155*6/110 = 93/11 sec

3. Single train + man in opposite direction problems questions:
A train which is a length of 110 meters travelling with a speed of 60 kmph. In what time it passes the man who is running with 6 kmph in opposite direction?
Here one thing you remember, in any train problems question they can mention two speed values in opposite direction then you can add that two values.
So in the above question speed = 60 kmph + 6 kmph = 66 kmph = 66*(5/18) = 55/3 m/s
D= 110 m, So time = 110/(55/3) = 110*3/55 = 6 sec
So the answer is 6 sec.

4. Single train + man in Same direction problems questions:
You can take same above question for this, But man is in same direction instead of opposite direction.
Here one thing you remember, in any train problems question they can mention two speed values in same direction then you can subtract that two values.
Speed = 60 kmph – 6 kmph = 54 kmph = 54*(5/18) = 15 m/s
Distance d = 110 m, So time = 110/15 = 22/3 sec

5. Two trains + opposite direction problems questions:
Two trains with different lengths, one is 137 meters and second is 163 meters are running towards each other. The speeds are also different that is one with a speed of 42 kmph and second is 48 kmph. In what time that two trains are crossed each other
This Train question problems is very lengthy but, answer for this question is very simple. As freshers junction explained above
Distance d = 137+163 = 300 m
Speed S = 48+42 = 90 kmph = 90*5/18 = 25 m/s    [Opposite direction]
Time = 300/25 = 12 sec.

6. Two trains + same direction problems questions:
You can take same above question for this, But the two trains are in same direction instead of opposite direction.
Distance d = 137+163 = 300 m
Speed S = 48-42 = 8 kmph = 8*5/18 = 20/9 m/s    [Same direction]
Time = 300/(20/9) = 300*9/20 = 270/2 = 135 sec

Click the link for more solved problems: Problems on Trains with Solutions – PDF