Wheel-Rail Interaction Introduction

[BEAUSABRE]

Interesting introduction to the engineering as to why rails and wheels are shaped like they are (5) Why Are Rails Shaped Like That? - YouTube

[BaltACD]

Here I thought I would find out why water is wet on rails? 

[Erik_Mag]

A lot of what the video covered was in the November 1967 issue of Model Railroader and Armstrong's book The Railroad, What it is, What it does. Having said that, his video did talk about what happens in the contact patch as well as mentioning the new AAR wheel profile and the benefits derived from it.