Question
What is total internal reflection ?
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Answer
Total Internal Reflection : When a light ray passes from a denser medium into a rarer medium it is deviated away from the normal i.e., angle of refraction will be greater than angle of incidence. It follows that for a particular value of the angle of incidence in the denser medium, the angle of refraction in the rarer medium will be 90° and this particular angle of incidence is known as critical angle and is denoted by $i_{c}$(as shown in adjacent fig).
For angle of incidence greater than critical angle, the angle of refraction will be greater than 90° and the ray will be reflected into the rarer medium in accordance with the laws of reflection. This phenomenon is called total internal reflection.
For angle of incidence greater than critical angle, the angle of refraction will be greater than 90° and the ray will be reflected into the rarer medium in accordance with the laws of reflection. This phenomenon is called total internal reflection.
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