2023 · Specimen · 5054/02 | Q5

0/45parts marked · 0 of 80 marks

Question (5 of 10)7 marks · Practise this topic →

Options

You may use a calculator. You should show all your working and use appropriate units. Take the weight of 1.0 kg to be 9.8 N (acceleration of free fall = 9.8 m/s²).

(a)

Fig. 5.1 shows light in air, incident on the side of a rectangular glass block at an angle of 60°.

Fig. 5.1: a ray enters a glass block at 60°, refracts at angle r and meets side XY at P with angle θ to the normal.

The refractive index of the glass is 1.6. The light travels in the glass and is incident on side XY at P.

Underline all the terms that describe a wave of light.

electromagnetic longitudinal radioactive transverse

[1 mark]

(b)

At the point where the light enters the glass, the angle of refraction is r.

Calculate angle r.

r = ......................................................... °

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]

(c)(i)

Calculate the critical angle c for light travelling in the block.

c = ......................................................... °

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]

(c)(ii)

At P, the angle θ between the ray and the normal is given by θ = 90° − r.

State and explain what happens to the light when it is incident on side XY.

Answer guidance

State A short answer. No explanation is needed, and adding one cannot earn extra marks.

[2 marks]

5054/02/SP/23Cambridge O Level Physics 5054 · Specimen 2023 · Paper 2 · Question 5