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

Solution

Length to covered by train = bridge length + its own length

$d=1000m+100m=1100m$

train speed = 45 km/hr = $45\times \frac{1000m}{3600hr}=12.5m/s$

so, time taken = $\frac{d}{v}=\frac{1100}{\left(12.5\right)}=88s$

Option - D is correct.