Page 256 - text book form physics kssm 2020

Formative Practice 6.2
6.2

1. Figure 6.28 shows the path of light which travels from air to a prism.
A

45°

45°
C B

Figure 6.28
(a) Determine the angle of refraction of light ray in the prism. Th e refractive index of
the prism is 1.50.
(b) Will the light ray experience total internal refl ection at the side AB of the prism?
Explain your answer.

2. Figure 6.29 shows a fi ne optical fi bre made up of inner core which has a high refractive
index surrounded by cladding material of a low refractive index.

n = 1.40 Cladding
cladding

n = 1.80
core
Inner core

Critical angle of
the optical fibre

Figure 6.29
(a) Determine the critical angle of the optical fi bre.
(b) What is the advantage of fi ne optical fi bre?

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