Question

The length of the bridge, which a train $150$ metres long and travelling at $54$ km/hr can cross in $40$ seconds, is

• A. $400$ m
• B. $450$ m
• C. $300$ m
• D. $350$ m

Answer 1

The correct option is B $450$ m

Speed of train $=54\times \frac{5}{18}=15$ m/s
Time taken $=40$ sec
Let the length of the bridge be $x$ metres.
Then, $\frac{150+x}{40}=15$
$\Rightarrow 150+x=600$
$\therefore x=450$ m