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
Volume solid wet film thickness is also 100 µm. Then after complete drying of the paint, the DFT will be 100 µm because no solvent will be evaporated. This is an important concept when using paint industrially to calculate the cost of painting. It can be said that it is the real volume of paint. Here is the formula by which one can calculate the volume solid of paint, In earlier days, the volume solid was measured by a disc method but now a sophisticated instrument is also available which takes only a drop of paint to check the volume solid. Volume