Available practice: 73 of 75 marks. Parts 7(a) await marking support. Scores cover available parts only. Theory Paper 2: Section A is compulsory and Section B offers a choice of two questions. Four published mark-scheme discrepancies across the two variants are held from automatic marking.
(a)Explain what is meant by critical angle.
Answer guidance
Explain Give reasons, not just what happens. Each distinct reason is usually worth a mark.
[2 marks]
(b)(i)Diamonds are attractive because of their ability to reflect light. The critical angle for diamond in air is 24°. Calculate the refractive index of diamond.
Answer guidance
Calculate Show your working. The method can earn marks even when the final value is wrong, and a bare answer often cannot.
[2 marks]
(b)(ii)The critical angle of diamond in air is 24°. In Fig. 6.1, continue each ray through its differently shaped diamond until the ray emerges into air.
[3 marks]
5054/21/M/J/16Cambridge O Level Physics 5054 · May/June 2016 · Paper 2 variant 1 · Question 6