Solid angle of its faces is one-sixth of that, or sr. Solid angles can also be measured in square degrees (1 sr = () square degrees), in square minutes and square seconds, or in fractions of the sphere (1 sr = fractional area), also known as spat (1 sp = 4 sr). In spherical coordinates there is a formula for the differential, where is the colatitude (angle from the North pole) and is the longitude. The solid angle for an arbitrary oriented surface S subtended at a point P is equal to the solid angle of the projection of the surface S
Solid surface such as metal alloys or polymers. Solid surfaces are synthetic surfaces manufactured from polymeric materials. Tools of surface fabrication include routers, drills, templates, clamps, ovens, suction cup grips, and table saws. Larger surface fabricators may also use CNC routers. For all but the simplest jobs, surface fabrication usually takes place in the workshop, after which the finished product is assembled and installed at the work site. Installation of multi-part surfaces, such as "L" and "U" shaped countertops, often involves complex work with specialized tools, to create a seamless result. Solid surfaces is used in the following environment : Solid surface