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प्रश्न
When a ray of light travels normal to the given surface, then the angle of refraction is ______.
विकल्प
180°
0°
90°
45°
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उत्तर
When a ray of light travels normal to the given surface, then the angle of refraction is 0°.
Explanation:
Traveling parallel to the normal is the refracted ray. Therefore, the angle of refraction is zero.
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