Question

A 100m long train is moving a cross a bridge of 300m at a speed of 90kmperh how much time it will take tocross the bridge compeletely

Answer 1

Hey.

Here is the answer.

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speed of train=90km/h =90×5/18m/s=25m/s
length of train =100m
length if bridge =300m

distance covered to cross the bridge= length of train + length of bridge =100+300=400m

as time= distance/speed
so, time =400/25 sec =16 sec
so, time taken to cross the bridge is 16sec.

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Thanks.

Answer 2

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

d = (100 + 300) m = 400 m

The speed of the train is,

v = 90 km/h = 90 × 5 / 18 = 25 m/s

Hence the time taken to cross the bridge is,

t = 400 / 25 = 16 s.