Question

5. Express the reation for solid angle​

Answer 1

Answer:

The angle subtended at the center of the sphere by the surface of the sphere is called solid angle.This is a three dimensional angle. Suppose area of the surface which makes a cone on the center (O) of the sphere is 'S' and the radius of sphere is r,then solid angle is defined as

S/r^2

The unit of solid angle is Steradian.

follow the figure above