Question

Two trains 121 m and 99 m in length, respectively, are running in opposite directions, one at a speed of 40 km/h and the other at a speed of 32 km/h. In what time will they be completely clear of each other from the moment they meet?

• A. 11 sec
• B. 10 sec
• C. 12 sec
• D. 13 sec

Answer 1

Answer:

A. 11 sec

total length of the train = (121 + 99) = 220 m As they are running in opposite directions having speeds of 40 km/h and 32 km/h respectively relative speed = (40 + 32) = 72 km/h = 72 × 5/18 = 20 m/s Time = Distance/Speed = 220/20 = 11