Two trains 110 m and 140 m long are running into same direction on a parallel track at the speed of 45 km/hr and 25 km/hr respectively . How much long the faster train will take to cross the slower train ( in sec ) ?
Answer & explanation
Correct answer: option 1
Total distance = 110 + 140 = 250 m
When trains moves in same direction, then relative speed = ( 45 - 25 ) = 20 km/hr
= 20 × \(\frac{5}{18}\) m/sec
Distance = Speed × Time
Time taken = \(\frac{250 \; × \; 18}{20 \; ×\; 5}\) = 45 sec.