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प्रश्न
Write a short note on the prisms making use of total internal reflection.
उत्तर
Prisms can be designed to reflect light by 90° or by 180° by making use of total internal reflection. The critical angle ic for the material of the prism must be less than 45°. This is true for both crown glass and flint glass. Prisms are also used to invert images without changing their size.
Prisms making use of total internal reflection
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