Contact Angle
The Angle 
between the normal vector of a Sphere (or other geometric object) at a point where aPlane is tangent to it and the normal vector of the plane. In the above figure,
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See also Spherical Cap
- NURBS Curve
- NURBS Surface
- Nyquist Frequency
- Nyquist Sampling
- Néron-Severi Group
- Nöther
- Obelus
- Object
- Oblateness
- Oblate Spheroid
- Oblate Spheroidal Coordinates
- Oblate Spheroidal Wave Function
- Oblate Spheroid Geodesic
- Oblique Angle
- Oblong Number
- Obstruction
- Obtuse Angle
- Obtuse Triangle
- Ochoa Curve
- Octacontagon
- Octadecagon
- Octagon
- Octagonal Number
- Octagram
- Octahedral Graph