A train crosses a platform 180 m long in 60 sec at a speed of 72 km/h. The time taken by the train to cross an electric pole is:
Answer & explanation
Correct answer: option 1
Let length of train = a meter
Speed = 72 km/h = 20 m/sec
Time = 60 sec
Distance = Speed × Time
= 20 × 60 = 1200 m
According to question
a + 180 = 1200
a = 1020
Now , Time to cross pole
Time = \(\frac{Distance}{Speed}\)
= \(\frac{1020}{20}\) = 51 sec