Aptitude - Problems on Trains - Discussion
Discussion Forum : Problems on Trains - General Questions (Q.No. 3)
3.
The length of the bridge, which a train 130 metres long and travelling at 45 km/hr can cross in 30 seconds, is:
Answer: Option
Explanation:
| Speed = |  |
45 x | 5 |  m/sec |
= | |
25 | m/sec. |
| 18 | 2 |
Time = 30 sec.
Let the length of bridge be x metres.
| Then, | 130 + x | = | 25 |
| 30 | 2 |
2(130 + x) = 750
x = 245 m.
Video Explanation: https://youtu.be/M_d8WufJWKc
Discussion:
250 comments Page 13 of 25.
Surekha said:
8 years ago
How would you say that bridge length would be more that train?
If bridge length is smaller than train means the answer would be vary.
If bridge length is smaller than train means the answer would be vary.
Sushi said:
1 decade ago
HEY. I have a doubt. The length of train is already covering some length of the bridge. Then why we consider both lengths separately?
Monika said:
1 decade ago
You can do this without any variable:
45 km/hr*5/18 = 25/2 m/s.
Total distance = 25/2*30 = 375.
Length of bridge = 375-130 = 245m.
45 km/hr*5/18 = 25/2 m/s.
Total distance = 25/2*30 = 375.
Length of bridge = 375-130 = 245m.
Santosh said:
9 years ago
No, WRONG ANSWER.
The correct answer is 115M.
X + 0.260km = 45 * 30/(60 * 60),
X + 0.26 = 0.375,
=> X= 0.115 KM = 115METERS.
The correct answer is 115M.
X + 0.260km = 45 * 30/(60 * 60),
X + 0.26 = 0.375,
=> X= 0.115 KM = 115METERS.
Atul said:
2 decades ago
Plz give me trick to solve to this. Bcz compny gives 1 minute /question and question is so lengthy, then how can I mange my time.
Abhi singh said:
7 years ago
So,
45 * 5/18 = 25/2 = 12.5.
Speed = 12.5,
Distance = time * speed = 30 * 12.5 = 375.
130+x = 375,
x = 375-130,
x = 245m/s.
45 * 5/18 = 25/2 = 12.5.
Speed = 12.5,
Distance = time * speed = 30 * 12.5 = 375.
130+x = 375,
x = 375-130,
x = 245m/s.
Akash S said:
5 months ago
A= 130m.
Speed of train = 45km/hr in 30 seconds.
45 = 30 * 5/18.
X = 150/18 * 45 m/s.
X = 375m/s.
Length = X - A.
375-130 = 245.
Speed of train = 45km/hr in 30 seconds.
45 = 30 * 5/18.
X = 150/18 * 45 m/s.
X = 375m/s.
Length = X - A.
375-130 = 245.
(21)
ARYAN said:
7 years ago
Length of the train = 130m.
speed =45km/h so, 45/3.6=12.5.
12.5*time=12.5*30=375m.
length of the bridge = [375-130] = 245m ANS.
speed =45km/h so, 45/3.6=12.5.
12.5*time=12.5*30=375m.
length of the bridge = [375-130] = 245m ANS.
(1)
Amit said:
9 years ago
Here, v = 45 km/hr = 45 * (1000/3600) = 25/2 m/s.
T = 30s.
S = vt = (25/2) * 30 = 375 m.
Now, L = 375 - 130 = 245 m (Ans).
T = 30s.
S = vt = (25/2) * 30 = 375 m.
Now, L = 375 - 130 = 245 m (Ans).
Dumpati Mahesh said:
1 decade ago
Here we should consider as per the problem that, Train is passing only one time through the bridge. So 130+B.L. Only sanjay.
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