JEE Mains · Physics · STD 12 - 9. Ray optics and optical instruments
In a long glass tube, mixture of two liquids A and B with refractive indices 1.3 and 1.4 respectively, forms a convex refractive meniscus towards \(A\). If an object placed at 13 cm from the vertex of the meniscus in A forms an image with a magnification of ' \(-2^{\prime}\) then the radius of curvature of meniscus is :
- A \(\frac{1}{3} \mathrm{~cm}\)
- B \(\frac{4}{3} \mathrm{~cm}\)
- C \(1\mathrm{~cm}\)
- D \(\frac{2}{3} \mathrm{~cm}\)
Answer & Solution
Correct Answer
(D) \(\frac{2}{3} \mathrm{~cm}\)
Step-by-step Solution
Detailed explanation
\begin{aligned} & \frac{\mathrm{n}_2}{\mathrm{v}}-\frac{\mathrm{n}_1}{\mathrm{u}} \frac{\mathrm{n}_2-\mathrm{n}_1}{\mathrm{R}} \\ & \frac{1.4}{\mathrm{v}}-\frac{1.3}{-13}=\frac{0.1}{\mathrm{R}} \\ & \frac{1.4}{\mathrm{v}}=\frac{1-\mathrm{R}}{10 \mathrm{R}} \\ &…
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