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 body against. This allows musicians to stop the string in the same place. Ebony, rosewood and maple are commonly used to make the fingerboard. Some electric guitar necks do not have a separate piece of wood for the fingerboard surface. All the solid bodies have variations in scale length or, the length of the strings from the nut to the bridge. The action, or the height of the strings from the fingerboard, is adjustable on solid body instruments. Most solid bodies have controls for volume and tone. Some have an electronic preamplifier with equalization for low, middle, and high frequencies. These