The plane faces of two identical plano-convex lenses each having focal – McqOptions

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1.	The plane faces of two identical plano-convex lenses each having focal length of 40 cm are pressed against each other to form a usual convex lens. The distance from this lens, at which an object must be placed to obtain a real, inverted image with magnification one is [NCERT 1980; CPMT 1981; MP PMT 1999; UPSEAT 1999]
A.	80 cm
B.	40 cm
C.	20 cm
D.	162 cm
Answer» C. 20 cm

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