Question

Two trains having length $200\text{m}$ and $332\text{m}$ are running in the opposite directions with velocities $54\text{km/h}$ and $72\text{km/h}$. In what time they will completely cross each other?

• A. $15.2\text{s}$
• B. $16.2\text{s}$
• C. $15.8\text{s}$
• D. $16.8\text{s}$

Answer 1

The correct option is C $15.8\text{s}$

The relative velocity of the two trains are as follows
$V=72–(–54)=126\text{km/h}=35\text{m/s}$
The total length of both the trains are $=200+332=552\text{m}$
Therefore, the time taken for them to cross each other $T=552/35=15.8\text{s}$