Question

a train 100m in length is running at a speed of 72km/h. What is the time taken by the train to cross a bridge of length 525m? in hour
1)0.087h
2)0.0087h​

Answer 1

Answer:

31.25 s

Step-by-step explanation:

According to the given question,

v = velocity = 72 km/h = 72×1000/3600 = 20 m/s

d = length of bridge = 525 m

l = length of train = 100 m

And we are asked to find the time taken by the train to cross the bridge.

Here,

s = distance = 525+100 = 625 m; is the total distance that train has to cover to cross the bridge.

We know,

distance = velocity×time

time = distance/velocity

Putting the values we get,

time = 625/20

time = 31.25 sec

Thus time taken by the train to cover the bridge is 31.25 sec.

Answer 2

Answer:

721x−8x=4

∴ 152x−8x=4

∴x=480km.