You've probably tried at some point to set a car in motion using only your own muscle power. Maybe you succeeded, but it was likely quite challenging. This wagon weighs 1.4 tonnes, about the same as a regular car.

The combination of railway tracks and steel wheels means that this wagon requires minimal force to start rolling. The contact area between the rails and wheels is very small, making it effortless!

Go ahead, see if you can get the wagon rolling with just one hand (or a finger). But remember, it’s heavy!