This is a question that would baffle many. It surely baffled us and we thought the flanges on the wheels keep the trains on the track, but that’s not the case at all. Then what could it be? Let’s try to address that exactly.
If you notice the shape of the wheel of a train, you will notice that they are conical in shape. The side with greater diameter is on the inside. The shorter diameter lies towards outside.When the train approaches a curve and has to turn then the wheels slide away in the correct direction. This keeps the train on the track and allows for proper negotiation of the curve.
The following takes place once a train is in motion :
In studying this theory we are considering that the train is moving in the left direction.Now if the train is making a left turn. Then the wheels due to centrifugal force will move towards the right. Obviously, this will result in an increase in diameter of the right wheel and decrease in diameter of the left wheel.
This will allow the right wheel to travel more distance due to the larger diameter when compared to the left wheel. Hence solving the problem. The simple design provides a genius solution every time.