Question
Solve the previous problem if the paperweight is inverted at its place so that the spherical surface touches the paper.
✓
Answer
Thickness of glass $=3\text{cm}, \ \mu_{\text{g}}=1.5$ Image shif $=3\Big(1-\frac{1}{1.5}\Big)$ [Treating it as a simple refraction problem because the upper surface is flat and the spherical surface is in contact with the object]$=3\times\frac{0.5}{1.5}=1\text{cm}.$The image will appear 1 cm above the point P.
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