Two train 110 m and 140 m long are running in same direction on a parallel track at the speed of 70 km/hr and 50 km/hr respectively. How long the faster train will take to cross the slower train?
Answer & explanation
Correct answer: option 4
To cross the train, total distance to be traveled = Sum of length of trains
Distance = 110 + 140 = 250 m
Relative speed in same direction = S1 - S2 = 70 - 50 = 20 km/hr = 20 × \(\frac{5}{18}\) m/sec
⇒ Time to cross the slower train = \(\frac{Distance}{Relative\;Speed}\)
= \(\frac{250\;×\;18}{20\;×\;5}\)
= 45 Sec.