For a transparent prism, if the angle of minimum deviation is equal to its refracting angle, the refractive index n of the prism satisfies.

Step-by-step solution

At minimum deviation, _m = A (angle of minimum deviation equals prism angle). The refractive index formula becomes: n = ( A + _m 2 ) ( A 2 ) = ( 2A 2 ) ( A 2 ) = A ( A 2 ) Using A = 2 ( A 2 ) ( A 2 ) : n = 2 ( A 2 ) ( A 2 ) ( A 2 ) = 2 ( A 2 ) For a physical prism, 0 Therefore, 1 < n < 2 2 = 2 2 . However, more precisely, 2 < n < 2 .