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Question
Solve the previous problem if the paperweight is inverted at its place so that the spherical surface touches the paper.
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Solution
Given,
Taking the radius of the paperweight as its thickness = 3 cm
Refractive index of the paperweight (μg) = 3/2
Refractive index of the air (μ1) = 1
Image shift is given by:
\[∆ t = \left( 1 - \frac{1}{\mu} \right)t\]
\[ = \left( 1 - \frac{2}{3} \right)3\]
\[ = \left( \frac{1}{3} \right)3\]
\[ = 1 \text{ cm }\]
The upper surface of the paperweight is flat and the spherical spherical surface is in contact with the printed letter.
Therefore, we will take it as a simple refraction problem.
Hence, the image will appear 1 cm above point A.
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