JEE MainPhysicsGeometrical OpticsMCQ+4 / −1
A planoconvex lens becomes an optical system of focal length when its plane surface is silvered and illuminated from left to right as shown in Fig-A. If the same lens is instead silvered on the curved surface and illuminated from other side as in Fig-B, it acts like an optical system of focal length The refractive index of the material of lens is : 
- A
- B
- C
- D
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