A light ray emerging form the point source placed at P(2,3) is reflected at a point Q on the y-axis. It then passes through the point R(5,10). The coordinates of Q are

The point of coincidence on the y-axis is Q(0,λ)The image of P(2,3) on the y-axis is P1(−2,3).P1,Q, and R are collinear.Therefore, Slope of P1,Q = slope of P1Ror λ−30−(−2)=10−35−(−2)or λ−3=2or λ=5Therefore, the point Q is (0,5)