Physics · 2019
JEE Main · 10 April 2019, Shift 1 · Q23
One plano-convex and one plano-concave lens of same radius of curvature ' R ' but of different materials are joined side by side as shown in the…
One plano-convex and one plano-concave lens of same radius of curvature ' $\displaystyle R$ ' but of different materials are joined side by side as shown in the figure. If the refractive index of the material of $\displaystyle 1$ is $\displaystyle \mu_1$ and that of $\displaystyle 2$ is $\displaystyle \mu_2$, then the focal length of the combination is :
Official answer
(1)
$\displaystyle \frac{\mathrm{R}}{\mu_1-\mu_2}$
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JEE Main 2019 Physics question, with the answer from NTA’s final answer key. Where our answers come from.