Physics · 2020
JEE Main · 8 January 2020, Shift 1 · Q25
A point object in air is in front of the curved surface of a plano-convex lens. The radius of curvature of the curved surface is 30 cm and the…
A point object in air is in front of the curved surface of a plano-convex lens. The radius of curvature of the curved surface is $\displaystyle 30$ cm and the refractive index of the lens material is $\displaystyle 1.5$ , then the focal length of the lens (in cm ) is \_\_\_\_.
Official answer
60
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JEE Main 2020 Physics question, with the answer from NTA’s final answer key. Where our answers come from.