A student is investigating the refraction and reflection of light in a transparent rectangular block. The theory suggests that a certain angle θ \theta\,θ and the angle of incidence i i\,i are related by the formula: θ=2i\theta = 2iθ=2i.
In the first run of the experiment, the angle of incidence is set to i=35∘i = 35^\circi=35∘. The student measures the angle θ \theta\,θ to be 71∘71^\circ71∘. (i) Calculate the value of 2i 2i\,2i for this run.
(ii) Calculate the difference (θ−2i)(\theta - 2i)(θ−2i) for this run.
In the second run of the experiment, the student uses an angle of incidence i=45∘i = 45^\circi=45∘ and obtains a measured value of θ=88∘\theta = 88^\circθ=88∘. Calculate the difference (θ−2i)(\theta - 2i)(θ−2i) for this run.
State whether the results from parts (a) and (b) support the theory that θ=2i\theta = 2iθ=2i. Justify your answer by referring to your calculated differences.
100 exam-style questions on CIE IGCSE Physics 3.2.2 Refraction of light. Each one has a worked solution and a mark scheme showing where the marks go.