Two trains each 100 meter long moving in opposite direction, cross each other in 8 seconds. If one is moving twice as fast as other, then the speed of the faster train is:
Answer & explanation
Correct answer: option 3
Total Distance to cross each other = sum of length of trains = 100 +100 = 200m
Time = 8 sec
Relative Speed = \(\frac{Total\;distance}{Total\;time}\) = \(\frac{200}{8}\) = 25 m/sec = 25 × \(\frac{18}{5}\) km/hr = 90 km/hr
ATQ,
⇒ Speed of faster train = 2R
⇒ Speed of slower train = 1R
⇒Relative speed in opposite direction = 2R + 1R = 3R
3R = 90 km/hr
1R = 30 km/hr
2R = 60 km/hr = Speed of faster train.