Aptitude - Problems on Trains - Discussion
Discussion Forum : Problems on Trains - General Questions (Q.No. 10)
10.
A jogger running at 9 kmph alongside a railway track in 240 metres ahead of the engine of a 120 metres long train running at 45 kmph in the same direction. In how much time will the train pass the jogger?
Answer: Option
Explanation:
Speed of train relative to jogger = (45 - 9) km/hr = 36 km/hr.
| = |  |
36 x | 5 |  m/sec |
| 18 |
= 10 m/sec.
Distance to be covered = (240 + 120) m = 360 m.
 Time taken = |
|
360 | sec |
= 36 sec. |
| 10 |
Discussion:
106 comments Page 4 of 11.
Ravi said:
4 years ago
Even the jogger is running at a particular speed and is not idle so why are we not considering the distance travelled by the jogger when the train passes him?
Please anyone clarify this.
Please anyone clarify this.
(6)
Rohit basuri said:
1 decade ago
The jogger is also running. So, we also need to factor in the additional distance he covers.
If the time taken by train to cross the jogger is x.
(360+(9*5/18)*x)/10 = x.
x = 48 sec.
If the time taken by train to cross the jogger is x.
(360+(9*5/18)*x)/10 = x.
x = 48 sec.
Karthik said:
2 decades ago
Relative speed= hidh speed + low speed when the objects are moving in the oppsite direction
Relative speed= hidh speed - low speed when the objects are moving in the same direction
Relative speed= hidh speed - low speed when the objects are moving in the same direction
Sailesh said:
9 years ago
They asked how much time the train pass jogger. Should the entire train pass the jogger (then distance=240 + 120) or should the engine only just pass the jogger (then distance =240).
Manojbatchu said:
1 decade ago
In how much time train crosses the jogger?
Then why they are adding the 240 m railway track length?
Jogger speed, train speed, train length enough. Please any one solve my doubt.
Then why they are adding the 240 m railway track length?
Jogger speed, train speed, train length enough. Please any one solve my doubt.
Aaditya said:
1 decade ago
For the 1st 240m. Why are calculating the relative speed?
The jogger comes alongside the train after 240m. So, after that the relative speed should be considered. Please explain.
The jogger comes alongside the train after 240m. So, after that the relative speed should be considered. Please explain.
Biswajit said:
1 decade ago
Dhanu,
You are right. As the jogger is also in motion so its speed should be considered and that changes the time significantly. I wonder why no one have pointed this earlier.
You are right. As the jogger is also in motion so its speed should be considered and that changes the time significantly. I wonder why no one have pointed this earlier.
Satish said:
8 years ago
@All.
Hi, I think the question is incorrect because if they are going in the same direction then train already ahead and has high speed than jogger so the train will go away.
Hi, I think the question is incorrect because if they are going in the same direction then train already ahead and has high speed than jogger so the train will go away.
Saurav said:
1 decade ago
Relative speed itself means that the speed of other object is 0. As we are finding the speed of the train relative to man. (45-9 = 36). So man has been made to be in rest.
Kevin said:
4 years ago
The distance to be covered is the length from the train to the jogger (240) And we are adding 120 because we need to know the time when the whole train passes the jogger.
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