Question

Two trains 140 m and 160 m long run in the opposite directions on parallel tracks at the speed of 60 km/hr and 40 km/hr respectively. Calculate the time they take to cross each other.

• A. 12 seconds
• B. 10 seconds
• C. 10.8 seconds
• D. 9.5 seconds

Answer 1

The correct option is C

10.8 seconds

Relative Speed = 60 + 40 = 100 kmph

= $\frac{100\times 5}{18}$ = $\frac{250}{9}$ m/sec

Distance = 140 + 160 = 300 meters

Time = $\frac{Distance}{Speed}$

Time = $\frac{300}{\frac{250}{9}}$ = $\frac{300\times 9}{250}$ = 10.8 seconds

So the time taken by the trains to cross each other is 10.8 seconds.