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प्रश्न
A rectangular block of glass ABCD has a refractive index 1.6. A pin is placed midway on the face AB (Figure). When observed from the face AD, the pin shall ______.
- appear to be near A.
- appear to be near D.
- appear to be at the centre of AD.
- not be seen at all.
विकल्प
a and c
a and d
b and d
c and d
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उत्तर
a and d
Explanation:
As long as angle of incidence on AD of the ray emanating from the pin is less than the critical angle, the pin shall appear to be near A.
When angle of incidence on AD of the ray emanating from pins is greater than the critical angle, the light suffers from total internal reflection and cannot be seen through AD.
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संबंधित प्रश्न
Name the factors affecting the critical angle for the pair of media.
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Swarali observed that the light bent away from the normal, while travelling from dense medium to rarer medium. When Swarali increased the values of angle of incidence (i), the values of angle of refraction (r) went on increasing. But at a certain angle of incidence, the light rays returned into the dense medium.
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