Question

a train 40m long passes over a bridge 200m long at a speed of 36 km/h. how long will it take to pass completely over the bridge?

Answer 1

total length to be covered = 200+40 =  240

speed =  36km/hr = 10m/s

therefore time taken = 240/10 = 24seconds

Answer 2

The "time taken" by the train to pass the bridge is 24 seconds.

Given data:

Length of the train = 40 m

Length of the bridge = 200 m

Speed = 36 km/hr

To find:

Time taken = ?

Solution:

Firstly convert the speed of train from km/h to m/s

$Speed =36 \times \frac{5}{18}=10 \ \mathrm{m} / \mathrm{s}$

Then,

Total distance to be traveled is the length of the train and length of the bridge,

$Distance = 200 \ m + 40 \ m = 240 \ m$

Thereby,  

$\text {Time taken} =\frac{\text { Distance }}{\text {speed}}=\frac{240}{10}$

$\text{Time} = 24 \ seconds$