Question

A 100 m long train is moving with a uniform velocity of 45 km/hr. The time taken by the train to cross a bridge of length 1 km is

• A. 58 s
• B. 68 s
• C. 78 s
• D. 88 s

Answer 1

The correct option is D 88 s

Length of train =100 m
Velocity of train =45 km/hr=45$\times \frac{5}{18}$=12.5 m/s
Length of bridge =1 km=1000 m
$\therefore$ Total length covered by train =1100 m
Time taken by train to cross the bridge $=\frac{1100}{12.5}$=88 sec