`"axis"_1(min) = "axis"_2(min) = C_"min" / (2*pi)`

3.30246506915683

This constant represents the NCAA's minimum short axis length corresponding to the circumference of a football and is defined by relationship between diameter and circumference to to be no less than approximately `3.302` inches.¹

Remember: `"Circumference" = pi * "Diameter" = pi * 2 * b = pi * 2 * c =>`

`b_"min" = c_"min" ="Circumference"_"min"/(2*pi)`

/attachments/482c62b0-3d0b-11e5-a3bb-bc764e2038f2/Official Footbal axes 1 or 2.png

Since we can approximate the football with an ellipsoid, the circumference through the plane of the `"axis"_1' and `"axis"_2' is related to `b` or `c` as: `C = pi * (2 * b)`

/attachments/482c62b0-3d0b-11e5-a3bb-bc764e2038f2/Ellipsoid.png

See also