A light ray is incident on a smooth reflecting surface making an angle of incidence 2i. If the angle of incidence is doubled, then the deviation of the light ray is equal to ______ .

A light ray is incident on a smooth reflecting surface making an angle

1.	A light ray is incident on a smooth reflecting surface making an angle of incidence 2i. If the angle of incidence is doubled, then the deviation of the light ray is equal to ______ .
Answer» 90-40i 90-2i 2i 180-8i Solution :Initial angle of incidence =2i Angle of incidence when doubled `=2xx2i=4i` Therefore, angle of deviation `=180-(4i+4i)=180-8i` HENCE, the CORRECT OPTION is (d)