Refraction of light
3.2.2What the syllabus asks of you
- Define and use the terms normal, angle of incidence and angle of refraction
- Define refractive index n as n = sin i / sin r; recall and use this equation
- Describe an experiment to show refraction of light by transparent blocks of different shapes
- Define the terms critical angle and total internal reflection; recall and use the equation n = 1 / sin c
- Describe experiments to show internal reflection and total internal reflection
- Describe the use of optical fibres, particularly in telecommunications, stating the advantages of their use in each context
Read the notes first
Chapter 3: Refraction of light
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Every question on Refraction of light, untimed, marked as you go.
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Choose the years and how many questions, then print it with the answers on separate pages.
41 questions
1May / June 2026 · Paper 11 · Q23Show mark scheme →
Adispersion
Brarefaction
Creflection
Drefraction
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2May / June 2026 · Paper 11 · Q24Show mark scheme →
AA
BB
CC
DD
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3May / June 2026 · Paper 11 · Q25Show mark scheme →
A1, 2 and 3
B1 and 2 only
C1 and 3 only
D2 and 3 only
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4May / June 2026 · Paper 12 · Q25Show mark scheme →
A0.73°
B26°
C38°
D42°
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5Oct / Nov 2025 · Paper 11 · Q22Show mark scheme →
Aair/water diagram
Bair/glass semicircle diagram
Cair/perspex prism diagram
Dair/glass lens diagram
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6Oct / Nov 2025 · Paper 11 · Q23Show mark scheme →
Adirection A
Bdirection B
Cdirection C
Ddirection D
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7Oct / Nov 2025 · Paper 12 · Q27Show mark scheme →
Ar = n sin i
Bi = n sin r
Csin r = n / sin i
Dsin r = sin i / n
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8Oct / Nov 2025 · Paper 12 · Q30Show mark scheme →
A15°
B30°
C45°
D60°
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9May / June 2025 · Paper 11 · Q23Show mark scheme →
AA
BB
CC
DD
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10May / June 2025 · Paper 12 · Q22Show mark scheme →
Aair glass c A
Bair glass c B
Cair glass c C
Dair glass c D
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11Oct / Nov 2024 · Paper 11 · Q25Show mark scheme →
AA
BB
CC
DD
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12Oct / Nov 2024 · Paper 12 · Q22Show mark scheme →
A57.5°
B58.0°
C60.9°
D61.6°
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13May / June 2024 · Paper 11 · Q24Show mark scheme →
A23°
B25°
C45°
D81°
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14Oct / Nov 2023 · Paper 11 · Q19Show mark scheme →
Aair glass A
Bair glass B
Cair glass C
Dair glass D
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15Oct / Nov 2023 · Paper 11 · Q20Also set in May / June 2018 Paper 11Show mark scheme →
ATotal internal reflection only occurs when light travels from air into glass.
BThe larger the refractive index of glass, the larger is the critical angle.
CWhen total internal reflection occurs, the angle of incidence is equal to the angle of reflection.
DWhen total internal reflection occurs, the angle of incidence is less than the critical angle.
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16Oct / Nov 2023 · Paper 12 · Q27Show mark scheme →
A30°
B50°
C52°
D57°
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17Oct / Nov 2023 · Paper 12 · Q28Show mark scheme →
AA
BB
CC
DD
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18May / June 2023 · Paper 11 · Q21Show mark scheme →
Asin i = \frac{\sin 41^\circ}{n}
Bsin i = \frac{n}{\sin 49^\circ}
Csin i = n \times \sin 41^\circ
Dsin i = n \times \sin 49^\circ
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19May / June 2023 · Paper 12 · Q20Show mark scheme →
A0.66
B1.15
C1.64
D1.83
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20May / June 2023 · Paper 12 · Q21Show mark scheme →
Adiagram A
Bdiagram B
Cdiagram C
Ddiagram D
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21Oct / Nov 2022 · Paper 12 · Q23Show mark scheme →
A[diagram A: angle r above surface, angle i below surface]
B[diagram B: angle r above surface, angle i below surface]
C[diagram C: angle r above surface, angle i below surface]
D[diagram D: angle r above surface, angle i below surface]
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22Oct / Nov 2021 · Paper 11 · Q20Show mark scheme →
AA
BB
CC
DD
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23May / June 2021 · Paper 11 · Q21Show mark scheme →
A22°
B37°
C41°
D45°
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24May / June 2021 · Paper 12 · Q24Also set in May / June 2021 Paper 11Show mark scheme →
ADiagram A
BDiagram B
CDiagram C
DDiagram D
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25Oct / Nov 2020 · Paper 11 · Q28Show mark scheme →
AIt travels back into the water with an angle of reflection equal to c.
BIt travels back into the water with an angle of reflection greater than c.
CIt travels into air with an angle of refraction greater than θ.
DIt travels into air with an angle of refraction smaller than θ.
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26Oct / Nov 2020 · Paper 12 · Q24Show mark scheme →
AThe frequency of the light waves decreases.
BThe speed of the light waves decreases.
CThe wavelength of the light waves increases.
DThe wavelength of the light waves remains unchanged.
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27May / June 2020 · Paper 11 · Q27Show mark scheme →
AA
BB
CC
DD
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28May / June 2020 · Paper 12 · Q31Show mark scheme →
AW has a greater refractive index than X and angle y is equal to the critical angle.
BW has a greater refractive index than X and angle z is equal to the critical angle.
CX has a greater refractive index than W and angle y is equal to the critical angle.
DX has a greater refractive index than W and angle z is equal to the critical angle.
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29May / June 2020 · Paper 12 · Q32Also set in May / June 2020 Paper 11Show mark scheme →
AGraph A: straight line through origin with positive gradient
BGraph B: straight line with negative gradient from sin i = 1.0 at sin r = 0 to sin i = 0 at sin r = 0.5
CGraph C: straight line with negative gradient from sin i = 0.6 at sin r = 0 to sin i = 0 at sin r = 1.0
DGraph D: straight line through origin with positive gradient
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30Oct / Nov 2019 · Paper 11 · Q26Show mark scheme →
A0°
B40°
C50°
D90°
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31Oct / Nov 2019 · Paper 11 · Q27Show mark scheme →
Ain P and in Q
Bin P only
Cin Q only
Din neither P nor Q
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32Oct / Nov 2019 · Paper 12 · Q25Show mark scheme →
Athe angle of incidence
Bthe angle of reflection
Cthe angle of refraction
Dthe critical angle
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33Oct / Nov 2018 · Paper 12 · Q25Show mark scheme →
Afocal length of a glass lens
Breflection in a plane mirror
Crefraction as light enters glass
Dtotal internal reflection
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34May / June 2018 · Paper 12 · Q29Show mark scheme →
Amagnifying glass
Boptical fibre
Cphotographic enlarger
Dprojector
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35Oct / Nov 2017 · Paper 12 · Q21Show mark scheme →
A31°
B33°
C40°
D75°
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36Oct / Nov 2017 · Paper 12 · Q22Also set in Oct / Nov 2017 Paper 11Show mark scheme →
Agreater than 70°; greater than 1.4
Bgreater than 70°; less than 1.4
Cless than 70°; greater than 1.4
Dless than 70°; less than 1.4
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37May / June 2017 · Paper 11 · Q27Show mark scheme →
AA
BB
CC
DD
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38May / June 2017 · Paper 11 · Q28Show mark scheme →
A10°
B23°
C40°
D50°
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39Oct / Nov 2016 · Paper 11 · Q24Show mark scheme →
A23, 12
B24, 12
C23, 13
D24, 13
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40May / June 2016 · Paper 11 · Q23Show mark scheme →
Aangle of refraction 34°, critical angle 42°
Bangle of refraction 34°, critical angle 60°
Cangle of refraction 38°, critical angle 42°
Dangle of refraction 38°, critical angle 60°
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41May / June 2016 · Paper 12 · Q21Show mark scheme →
A\frac{\sin w}{\sin y}
B\frac{\sin w}{\sin z}
C\frac{\sin y}{\sin w}
D\frac{\sin z}{\sin x}
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