How does a Scalextric car work?

Scalextric cars work by using the metal conductor on the track as an electrical circuit. The cars have conductors on the underside which conduct the electricity from the mains on the wall. After conducting the electricity, it then passes through the motor of the car turning a small cog which then turns two other larger cogs. These cogs are attached to the wheels which then use friction to propell the car across the track! SIMPLE!