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General
Easy
Question
A paraxial beam of light is converging towards a point P on the screen. A plane parallel sheet of glass of thickness t and refractive index m is introduced in the path of beam. The convergence point is shifted by :
- t (1 – 1/
) away
- t (1 + 1/) away
- t (1 – 1/) nearer
- t (1 + 1/) nearer
) away
) away
) nearer
) nearer
The correct answer is: t (1 – 1/) away
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