JEE Mains · Physics · STD 12 - 9. Ray optics and optical instruments
Two immiscible liquids of refractive indices \(\frac{8}{5}\) and \(\frac{3}{2}\) respectively are put in a beaker as shown in the figure. The height of each column is \(6 \mathrm{~cm}\). A coin is placed at the bottom of the beaker. For near normal vision, the apparent depth of the coin is \(\frac{\alpha}{4} \mathrm{~cm}\). The value of \(\alpha\) is__________.
- A \(64\)
- B \(85\)
- C \(65\)
- D \(31\)
Answer & Solution
Correct Answer
(D) \(31\)
Step-by-step Solution
Detailed explanation
\(\mathrm{h}_{z p p}=\frac{\mathrm{h}_1}{\mu_1}+\frac{\mathrm{h}_2}{\mu_2}=\frac{6}{3 / 2}+\frac{6}{8 / 5}=4+\frac{15}{4}=\frac{31}{4} \mathrm{~cm}\)
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