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General
Easy
Question
The effective focal length of the lens combination shown in figure is -60 cm. The radii of curvature of the curved surfaces of the plano-convex lenses are 12 cm each and refractive index of the material of the lens is 1.5. The refractive index of the liquid is
- 1.33
- 1.42
- 1.53
- 1.60
The correct answer is: 1.60
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