A thin convex lens of focal length 10 cm is placed in contact with a c – McqOptions

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1.	A thin convex lens of focal length 10 cm is placed in contact with a concave lens of same material and of same focal length. The focal length of combination will be [CPMT 1972; 1988]
A.	Zero
B.	Infinity
C.	10 cm
D.	20 cm
Answer» C. 10 cm

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