Question

A train traveling at a uniform speed clears a platform 200 m long in 10 seconds and passes a telegraph post in 5 second .the speed of the train is

Answer 1

40 m/s is the right answer.

Here's how-

While passing the pole the train covers a distance of its own length.(Imagine yourself being 6 feet tall and passing through the pole while lying on ground. You'll know the distance covered while passing the pole will be your length, i.e 6 feet)

In the second case,the length covered while passing the station will be the length of station+the length of the train. (Imagine yourself lying and passing through station and you'll know how.)

Let length of train be x

speed is constant and is equal to distance÷time

so will be equal in both cases

distance 1÷time 1 is equal to distance 2÷ time 2

X÷5 = (X+200)÷10

solve for X=200

Speed equal distance÷time = X÷5 = 40 m/s

If you forget writing the unit in exam,I'll regret my 17 minutes of typing for the answer. Don't do that