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Questions
What is meant by the term ‘critical angle’?
What is a critical angle?
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Solution
It is the angle of incidence in the denser medium corresponding to which the angle of refraction in the rarer medium is 90°.
RELATED QUESTIONS
A ray of light travels from water to air as shown in the diagram given below :

1) Copy the diagram and complete the path of the way. Given the critical angle for water is 48°.
2) State the condition so that internal reflection occurs in the above diagram.
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1) Show in the diagram the path of these rays after striking the water surface.
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