Question:medium
A planoconvex lens fits exactly into a planoconcave lens. Their planar surfaces are parallel to each other. If the lenses are made of different materials of refractive indices mu₁ and mu₂ and R is the radius of curvature of the curved surface, then focal length of the combination is
A planoconvex lens fits exactly into a planoconcave lens. Their planar surfaces are parallel to each other. If the lenses are made of different materials of refractive indices mu₁ and mu₂ and R is the radius of curvature of the curved surface, then focal length of the combination is
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When lenses are in contact, powers add algebraically.
Updated On: Mar 20, 2026
- \( \dfrac{R}{\mu_1 - \mu_2} \)
- \( \dfrac{2R}{\mu_1 - \mu_2} \)
- \( \dfrac{R}{2(\mu_1 - \mu_2)} \)
- (R)/(2-(mu₁+mu₂))
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The Correct Option is A
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