Dave Plowman wrote:

Huge wrote:

The - Bits - Of - The - Tyre - Not - In - Contact - With - The - Road -
Are - Irrelevant. The - Only - Thing - That - Matters - Is - The -
Diameter - Of - The - Circle - Whose - Radius - Is - The - Distance -
From - The - Axle - To. The - Road.

You should have used caps, Huge. For those whose physics are still at
kindergarten level.

Except there isn't a single distance from the centre of the axle to all
parts of the tyre in contact with the road ... the average distance perhaps?