Question

Two trains travel in opposite directions at $36$ km/hr and $45$ km/hr respectively. A man sitting in the slower train passes the faster train in $8$ s. The length of the faster train is

• A. $80$ m
• B. $120$ m
• C. $150$ m
• D. $180$ m

Answer 1

Answer: (D)

$180$ m

As the trains travel in opposite direction then

Relative speed$=(45+36)km/hr=(81\times \frac{5}{18})m/sec=\left(\frac{405}{18}\right)m/sec$

$\therefore$ length of the faster train$=\frac{405}{18}\times 8=180m$