Aptitude - Problems on Trains - Discussion

Length of train = speed * time.
= 9 * 60 * 5/18(converting km/hr into m/sec).
= 150 meters.

Given;

60 km = 60 * 1000 = 60,000m
1 Hr = 60 * 60 = 3600 Sec.
Solution:

60,000/3600 * 9 Sec. = 150m.

Speed = (60 x 5/18)m/sec=(50/3)m/sec.
Length of the train = (Speed x Time).
Length of the train = (50/3 x 9)m = 150 m.

Thanks everyone for explaining the answer.

Speed 60 km/hr.
Time = 9 sec.

1. Convert speed into m/sec.
ie, Speed/3.6 => 60/3.6=16.67 m/sec.

2. To find the length.
Length L =Speed x time.
ie, L= 16.67 x 9 =150.
So the length of the train is 150 m.

Thanks for explaining the answer.

Length of train = speed * time.
= 9 * 60 * 5/18(converting km/hr into m/sec).
= 150 meters.

60km/hr = 5/18 * 60 m/s = 50/3 m/s.
50m/s means 50 metres for 3 seconds,
Then for 9 seconds - 150 metres.

Thanks all for giving a clear explanation.

if the start line and finish line are same then the time it will take to cross the line is equal to (the length of the vehicle/speed of the vehicle) that crossed the line.

The train took 9 seconds to cross the same line. It is travelling at the speed of 60 km/hr.

60 km/hr means "it took an hour to travel 60 kms."
60 km/hr = 60 km/1 hr.
= 60,000 m/60 mins.
= 60,000 m/3600 sec.
= 600 m/36 sec.
= 50 m/3 sec = 50/3 m/s.

Let length be (l)

Time taken = length/Speed.
9 sec = (l)metres/(50/3)m/s.
(l) Metres = 9 sec * (50/3) m/s.
(l) = 450/3 metres.
(l) = 150 metres.

The length of the train is 150 metres.