# Sphone (EntityTopic, 11)

(Redirected from Rotope 21)

A sphone is a special case of a pyramid where the base is a sphere. It contains the base sphere and a 3-D surface.

## Equations

• Variables:
r ⇒ radius of base of sphone
h ⇒ height of sphone
• All points (x, y, z, w) that lie on the surcell of a sphone will satisfy the following equations:
Unknown
• All points (x, y, z) that lie on the faces of a sphone will satisfy the following equations:
x2 + y2 + z2 = r2
w = 0
total edge length = 0
total surface area = 4π · r2
surcell volume = 3 · r2 · (r+√(r2+h2)
bulk = π3 · r3h
[!x,!y,!z] ⇒ cone
[!w] ⇒ sphere of radius (rnrh)

 Notable Tetrashapes Regular: pyrochoron • aerochoron • geochoron • xylochoron • hydrochoron • cosmochoron Powertopes: triangular octagoltriate • square octagoltriate • hexagonal octagoltriate • octagonal octagoltriate Circular: glome • cubinder • duocylinder • spherinder • sphone • cylindrone • dicone • coninder Torii: tiger • torisphere • spheritorus • torinder • ditorus

 16. 1111Tesseract 17. 31Sphone 18. [21]1Cylindrone List of tapertopes