1) A ray of light travelling in the direction 12(ˆi+√3ˆj) is inciodent on a plane mirror. after reflection, it travels along the direction 12(ˆi−√3ˆj) . The angle of incidence is A) 300 B) 450 C) 600 D) 750 Answer: Option AExplanation:Component along the plane=1/2 and component perpendicular to the plane = √32 ∴ tani=(12)(√32)=1√3 ∴ i= 300 = angle of incidence