Aptitude - Problems on Trains - Discussion
Discussion Forum : Problems on Trains - General Questions (Q.No. 2)
2.
A train 125 m long passes a man, running at 5 km/hr in the same direction in which the train is going, in 10 seconds. The speed of the train is:
Answer: Option
Explanation:
| Speed of the train relative to man = |  |
125 |  m/sec |
| 10 |
| = | |
25 | m/sec. |
| 2 |
| = | |
25 | x | 18 | km/hr |
| 2 | 5 |
= 45 km/hr.
Let the speed of the train be x km/hr. Then, relative speed = (x - 5) km/hr.
x - 5 = 45 
x = 50 km/hr.
Discussion:
475 comments Page 10 of 48.
Pradeep said:
1 decade ago
From The Question 5Km/hr So please explain it 1000/3600. give me reason.
KIRUBHA said:
1 decade ago
FRNDS is it correct or not tell me plz....
MAN'S SPEED = 5 KM/HR
Train length =125 m.
let assume train speed=x.
then we get relative speed (rs) of train and man is become
rs=x-5.
To conver km/hr into m/s.
= (x-5) / (5/18)
= 5x-25 / 18
speed = distance/time
125/10 = 5x-25 / 18
2250 = 50x-250
x = 2000 / 50
x = 40
Is it correct?
MAN'S SPEED = 5 KM/HR
Train length =125 m.
let assume train speed=x.
then we get relative speed (rs) of train and man is become
rs=x-5.
To conver km/hr into m/s.
= (x-5) / (5/18)
= 5x-25 / 18
speed = distance/time
125/10 = 5x-25 / 18
2250 = 50x-250
x = 2000 / 50
x = 40
Is it correct?
Swapnil....... said:
1 decade ago
Why is it addition of 45km/hr & 5km/hr?
Because I thing train & man is going to same direction that time sutract but in this case addition of 45km/Hr & 5km/hr please explain it why is it addition.
Because I thing train & man is going to same direction that time sutract but in this case addition of 45km/Hr & 5km/hr please explain it why is it addition.
Challu said:
1 decade ago
Think you are in a train, another one moving side by you in parallel, what will you experience? the train is in less speed of actualone. To find original speed you have to add your train speed.
Preethi said:
1 decade ago
You are right kirubha. Nice explanation challu.
Preethi said:
1 decade ago
Thanks Abhishek now I clear about relative speed.
Hari said:
1 decade ago
Excuse me? Why we divided 125 with 10?. Please explain me.
Ahmed said:
1 decade ago
Explanation given by ramesh chandra is very good and short, Please follow his process without wasting your time.
We need such a good explanation like that.
We need such a good explanation like that.
Uma said:
1 decade ago
Manoj explanation s superb. Thank you.
Vinod salunke said:
1 decade ago
Nice explanation by ramesh chandra.
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