Edexcel IGCSE Physics · Spec 3.18-3.20
Refractive Index & Total Internal Reflection
Refractive index and total internal reflection.
Physics revision video
Refractive Index & Total Internal Reflection
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Spec 3.18-3.20
What you need to know
- Understand refractive index n
- Explain total internal reflection
- Describe the critical angle and its uses
Active recall
Quick check
Answer each question before opening the answer.
What is the critical angle?
The angle of incidence in the denser medium above which total internal reflection occurs.
What two conditions are needed for total internal reflection?
Light must travel from a denser to a less dense medium, and the angle of incidence must exceed the critical angle.
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