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प्रश्न
Locate the image of the point P as seen by the eye in the figure.

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उत्तर
Given,
From the figure we can infer that the air is present in between the sheet, so it does not affect the shift. Therefore, the shift is only due to 3 sheets of different refractive indices, which is given by:
\[∆ t = \left[ 1 - \frac{1}{\mu_1} \right] t_1 + \left[ 1 - \frac{1}{\mu_2} \right] t_2 + \left[ 1 - \frac{1}{\mu_3} \right] t_3\]
\[= \left[ 1 - \left( \frac{1}{12} \right) \right]\left( 0 . 2 \right) + \left[ 1 - \left( \frac{1}{1 . 3} \right) \right]\left( 0 . 3 \right) + \left[ 1 - \left( \frac{1}{1 . 4} \right) \right]\left( 0 . 4 \right)\]
= 0.2 cm
Hence, location of image of point P is located 0.2 cm above point P.
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