Why does the calcualtion include the perimeter squared (P^2) and not the perimeter?

This ratio is designed to produce a *dimensionless measure
*of the shape. A dimensionless shape appears when taking the
ratio removes the dimensions of measurement.

Example: **6 meters/ 2 meters =
3**

Or, in our case: **(6 meters)^2/3 meters^2
= 36 meters^2/3 meters^2 = 12.**

This then presents the image in terms of its
*shape* and not its measurements of *size*.