A beam of white light is partially reflected and partially refracted from a surface. The angle between the reflected and refracted light is 90^ . The angle of refraction is 30^ . The angle of incidence must be

Step-by-step solution

Consider the following figure: Take angle of incidence i , angle of reflection r and angle of refraction r_ F =30^ Given from geometry: aligned & r+r_ F +90^ =180^ & r=90^ -r_ F aligned Since, angle of incidence is equal to the angle of reflection: i=r=90^ -r_F=90^ -30^ =60^