Question

a train 100m long is to cross a river of Bridge length 800m what time will it take to cross the bridge? The train move with a constant velocity of 36 km per hour

Answer 1

Hii..
Here is your answer..

Solution:-
Length of train=100m
Length of bridge=800m
So,Total Distance =800m+100m=900m

Speed =36km/h
In order to convert it in m/s we will multiple it with 5/18
$= > 36 \times \frac{5}{18} \\ = > 10$
So, Speed =10m/s
Now,
Time =?
Since we know that,
$speed = \frac{distance}{time} \\ time = \frac{distance}{speed} \\ = > \frac{900}{10} \\ = > 90$
Therefore,
Time =90seconds
We can write it as 1min 30seconds

Hope it helps uh...✌️✌️✌️

Answer 2

Total distance required for the train to cross the bridge is,

d = (100 + 800) m = 900 m

The speed of the train is,

v = 36 km/h = 36 × 5 / 18 = 10 m/s

Hence the time taken to cross the bridge is,

t = 900 / 10 = 90 s.