jee_main_2026_28_january_morning - Ray Optics and Optical Instruments Topics

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QUESTION #36 Lens Maker's Formula
The magnitudes of power of a biconvex lens (refractive index 1.5) and that of a plano-concave lens (refractive index = 1.7) are same. If the curvature of plano-concave lens exactly matches with the curvature of back surface of the biconvex lens, then ratio of radius of curvature of front and back surface of the biconvex lens is ____.
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QUESTION #49 Lens in Liquid
A convex lens of refractive index 1.5 and focal length f = 18 mathrm~cm is immersed in water. The difference in focal lengths of the given lens when it is in water and in air is alpha times f . The value of alpha is ____. (refractive index of water = 4/3)
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JEE Physics: Waves (+15.5%) | Electrostatics: Concentric Shells (-29.7%) | Modern Physics: Photoelectric Clones (+34.2%) | Mathematics: Definite Integrals (+18.1%) | Chemistry: Coordination Splitting (-11.4%) | JEE Physics: Waves (+15.5%) | Electrostatics: Concentric Shells (-29.7%) | Modern Physics: Photoelectric Clones (+34.2%) | Mathematics: Definite Integrals (+18.1%) | Chemistry: Coordination Splitting (-11.4%)
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