Fig. 7.1 depicts a light ray striking a rectangular glass block at point X. The ray is refracted at X. In the diagram, W is the incident ray, the region above the block is air, the material inside is glass, and P, Q, R and S mark the corners.
(a)[1]
At X on Fig. 7.1, draw the normal.
(b)[1]
On Fig. 7.1, draw the route of the ray through the glass block until it arrives at the surface RS.
(c)[2]
On Fig. 7.1, at X, label the angle of incidence with $i$ and the angle of refraction with $r$.
(d)[1]
On Fig. 7.1, draw the path taken by the ray of light as it leaves the glass block.
Worked solution & mark scheme
This 5-mark question has a full step-by-step worked solution and mark scheme. One marking point: “normal shown at X, extending above and within the block” …