Aptitude - Problems on Trains - Discussion
Discussion Forum : Problems on Trains - General Questions (Q.No. 1)
1.
A train running at the speed of 60 km/hr crosses a pole in 9 seconds. What is the length of the train?
Answer: Option
Explanation:
| Speed = |  |
60 x | 5 |  m/sec |
= | |
50 | m/sec. |
| 18 | 3 |
Length of the train = (Speed x Time).
 Length of the train = |
|
50 | x 9 | m = 150 m. |
| 3 |
Discussion:
584 comments Page 1 of 59.
Sundar said:
2 decades ago
Why we are multiplying the 60 with 5/18?
The answer is simple. We are converting the 'kilo-meters/hour' value into 'meters/second'.
Let me explain about converting km/hr into m/s in detail.
1 km = 1000 meters.
1 hr = 3600 seconds.
1 km/hr = 1000/3600 m/s
= 10/36 m/s
= 5/18 m/s.
Therefore 1 km/hr = 5/18 m/sec.
Similarly 60 km/hr = 60 x 5/18 m/sec.
You may ask me, why should I convert it from km/hr to m/sec?
Because, the time taken by the train is given in terms of seconds (9 seconds) and the 4 options are in terms of metres. But the speed of the train is given in terms of km/hr. So we have to convert the values from km/hr to m/s in order to find the solution in terms of metres/seconds.
Hope you understand better. Have a nice day guys!
The answer is simple. We are converting the 'kilo-meters/hour' value into 'meters/second'.
Let me explain about converting km/hr into m/s in detail.
1 km = 1000 meters.
1 hr = 3600 seconds.
1 km/hr = 1000/3600 m/s
= 10/36 m/s
= 5/18 m/s.
Therefore 1 km/hr = 5/18 m/sec.
Similarly 60 km/hr = 60 x 5/18 m/sec.
You may ask me, why should I convert it from km/hr to m/sec?
Because, the time taken by the train is given in terms of seconds (9 seconds) and the 4 options are in terms of metres. But the speed of the train is given in terms of km/hr. So we have to convert the values from km/hr to m/s in order to find the solution in terms of metres/seconds.
Hope you understand better. Have a nice day guys!
(67)
Karthick said:
2 decades ago
Nice explanation for beginners.
(7)
Dhesappan said:
1 decade ago
Any one know the how many feet is one meter?
(2)
Sundar said:
1 decade ago
Feet to Meter conversion: 1 feet = 0.3048 meter
Meter to Feet conversion: 1 meter = 3.28083 feet
Meter to Feet conversion: 1 meter = 3.28083 feet
(2)
Jain Thomas said:
1 decade ago
Hi Sundar,
That was a damn good explanation
That was a damn good explanation
(1)
Rita said:
1 decade ago
Very well explained Sundar. Thanks a lot for helping us with your valuable explanation
(2)
Kalimuthu said:
1 decade ago
1000m=1km so 60000m goes in 1hour.
1 hour=3600 sec so 60000/3600 =16.666 so train cross in 1 second is 16.666m...so 9 seconds 16.6666*9=150meter .
1 hour=3600 sec so 60000/3600 =16.666 so train cross in 1 second is 16.666m...so 9 seconds 16.6666*9=150meter .
(7)
B.V.S.SHARMA said:
1 decade ago
60*5/18*9=150 m...
Parashuram said:
1 decade ago
How to calculate 16*5/18*9?
(1)
V.Navin kumar said:
1 decade ago
Nice to learn fast.
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