Question

Two trains are running towards each other on parallel lines having length of 184 m and 270 m. The speeds of the train are 71 km/h and 55 km/h respectively. In what time they will be clear of each other from the moment they meet?

• A. 15 Sec
• B. 18 Sec
• C. 13 Sec
• D. 09 Sec

Hint:

Track how each new volume of Chemical B affects the existing mixture ratio.

Answer 1

The Correct Option is C

When two trains move toward each other, the relative speed at which they close the gap is the sum of their individual speeds: \(71+55=126\) km/h, which converts to \(126 \times \dfrac{5}{18} = 35\) m/s.
For the trains to fully clear each other after meeting, the combined length of both trains needs to pass at that relative speed: \(184+270=454\) m.
Time taken is \(454/35 \approx 13\) seconds, matching option 3.