A green light with frequency $5.7 \times 10^{14}\,\text{Hz}$ moves through air at a speed of $3.0 \times 10^8\,\text{m s}^{-1}$. It strikes the surface of a transparent solid. Fig. 6.1 presents the wavefronts together with the direction of motion of the light in air. The light moves more slowly in the transparent solid.
(a)[3]
Explain, in terms of the wavefronts, why the light changes direction when it enters the solid. You may annotate Fig. 6.1 in your response.
(b(i))[2]
Calculate the angle of refraction of the light in the solid.
(b(ii))[4]
Determine the wavelength of the green light in the material.
Worked solution & mark scheme
This 9-mark question has a full step-by-step worked solution and mark scheme. One marking point: “One edge of the wavefront enters the solid before the other” …