DP Physics (last assessment 2024)
Question 17N.3.HL.TZ0.a
Date | November 2017 | Marks available | [Maximum mark: 3] | Reference code | 17N.3.HL.TZ0.a |
Level | HL | Paper | 3 | Time zone | TZ0 |
Command term | Calculate | Question number | a | Adapted from | N/A |
a.
[Maximum mark: 3]
17N.3.HL.TZ0.a
Some optic fibres consist of a core surrounded by cladding as shown in the diagram.
Calculate the maximum angle β for light to travel through the fibre.
Refractive index of core = 1.50
Refractive index of cladding = 1.48
[3]
Markscheme
realization that 𝜃 min is the critical angle
𝜃 = «sin–1 =» 80.6 «°»
Accept 1.4 rad
β = «90 – 80.6 =» 9.4 «°»
Accept 0.16 rad
