Fig. 3.1 illustrates three light rays moving through water from a light source S. At the water-air boundary, one of the rays is totally internally reflected.
(a)[1]
On Fig. 3.1, mark the critical angle, then label it $c$.
(b)[1]
State why just one of the three rays is totally internally reflected.
(c(i))[2]
Calculate the refractive index of water.
(c(ii))[2]
Calculate the critical angle at the water-air boundary.
Worked solution & mark scheme
This 6-mark question has a full step-by-step worked solution and mark scheme. One marking point: “The angle of incidence for the middle ray is labelled c” …