Two trains each 365 meter long, are running in opposite directions on parallel tracks. If their spee

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27 Oct 2017 Trains

Two trains each 365 meter long, are running in opposite directions on parallel tracks. If their speeds are 44 km/hr and 64 km/hr respectively, the square of time taken by the faster train to pass the driver of the slower one is?

OPtion

1) 12.55 seconds
2) 12.31 seconds
3) 12.93 seconds
4) 12.00 seconds
5) 12.16 seconds
6) 142.50 seconds
7) 144.26 seconds
8) 148.03 seconds
9) 149.01 seconds
10) None of these

Solution

Relative speed= 64+44 = 108 km/hr = 108 * 5/18 = 30 m/sec

We are calculating the time taken by the faster train to pass the driver of the slower one.
Hence, distance = length of the faster train = 365 metre

Time = 365/30 = 12.16 seconds
Square of time taken = (365/30) ^2 = 148.03

Option 8)

Correct Option: 8 Best Solution (5)

Dr.Dipin Singh   7 years AGO

Relative velocity of trains= 64+44=108 km/hr= 30m/sec
Time taken by faster train to pass the driver of slower train = 365/30 = 73/6 secs = 12.16666.. secs
Square of this time = 148.027777... secs =148.03 seconds

Like? Yes (8) | No   

G.S.Kantharao   7 years AGO

Relative speed per second=(64+44)5/18=30mts/sec
Time taken to cross the driver = time taken to travel 1 length=365m
Time taken =12.16667sec
It's square=148.03 sec
Hence my option is 8👈

Like? Yes (4) | No (2)  

Smriti shikha   7 years AGO

to cross the driver the faster train has to cover 365 m.
time taken=365 /(108* 5/18) = 12.166
12.166^2= 148.0277
option 8 is correct

Like? Yes (1) | No   

SAYAN CHATTERJEE   7 years AGO

Total distance to be covered= 0.365 km.
The relative velocity is (44+64)= 108km/hr.
So, time take = (0.365/108)*3600 secs. = 12.17 secs.
So, square of the time taken = 12.17^2 = 148.03 sec^2.
Option 8.

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AYAN PAUL   7 years AGO

Relative speed of the two trains is 30 m/sec
Now the time taken by the faster train to cross the driver of the slower train is = 365/30 = 12.16 sec
So square of it will be = 148.03 sec

Like? Yes (3) | No (3)