Question

A 50m long cross over a bridge at a speed of 30km/hr if it takes 30 sec to cross the bridge. What is the length of the bridge

Answer 1

let length​ of bridge be b meters.

so speed of train= distance/time

=> length of train+length of bridge / time take to cross the bridge

=> (50+b)/36 = 30*5/18 ← converting from kmph to mps

=> 50+ b = 300

=> b = 250m

so the length of the bridge is 250m