If in a plano-convex lens, the radius of curvature of the convex surface is 10 cm and the focal length of the lens is 30 cm , then the refractive index of the material of lens will beA. 20.5 cmB. 10 cmC. 15.5 cmD. 5 cm

If in a plano-convex lens, the radius of curvature of the convex surfa

1.	If in a plano-convex lens, the radius of curvature of the convex surface is 10 cm and the focal length of the lens is 30 cm , then the refractive index of the material of lens will beA. 20.5 cmB. 10 cmC. 15.5 cmD. 5 cm
Answer» Correct Answer - B (b) Focal length,F=`R/(2(µ-1))` `rArrF=10/(2(15-1))=10cm`

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If in a plano-convex lens, the radius of curvature of the convex surface is 10 cm and the focal length of the lens is 30 cm , then the refractive index of the material of lens will beA. 20.5 cmB. 10 cmC. 15.5 cmD. 5 cm

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