A plano convex lens fits exactly in to a plano concave lens. Their plane surfaces are parallel to each other. If the lenses are made of different materials of refractive indices mu_1 andmu_2 and 'R' is the radius of curvature of the curved surfaces of the lenses then the focal length of the combination is

A plano convex lens fits exactly in to a plano concave lens. Their pla

1.	A plano convex lens fits exactly in to a plano concave lens. Their plane surfaces are parallel to each other. If the lenses are made of different materials of refractive indices mu_1 andmu_2 and 'R' is the radius of curvature of the curved surfaces of the lenses then the focal length of the combination is
Answer» `(R )/(mu_1 - mu_2)` `(2R)/(mu_1 - mu_2)` `(R )/(2(mu_1 - mu_2))` `( R)/(mu_1 + mu_2)` ANSWER :A

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