Fig. 5.1 shows four red-light rays, P, Q, R and S, leaving a spotlight in a swimming pool. The diagram is labelled spotlight, water, air, and rays P, Q, R, S.
(a)[1]
Define, in words, refractive index for a ray of light moving from air into water.
(b)[2]
On Fig. 5.1, draw the paths of rays P and Q at the water-air boundary.
(c)[2]
Calculate the refractive index for the water.
(d)[2]
Explain why ray S is totally internally reflected at the water surface.
Worked solution & mark scheme
This 7-mark question has a full step-by-step worked solution and mark scheme. One marking point: “refractive index is the quotient of the speed of light in two different media” …