Question

a train 100 M long moving on a straight level train passes a pole in 5 seconds find the speed of the train and the time it will take to cross a bridge 500 m long

Answer 1

A train passes the pole in 5 sec. it's means The train cover itself in 5 sec.
So we can say that A train covers 100 m in 5 sec.
So we have find that time to cover 500 m long bridge.
so.. 5/100 x 500 = 25 sec
​Speed = Distance/Time
=> Speed = 500 m /25 sec
=> Speed = 20 m/sec