Two thin lenses, one of focal length + 60 cm and the other of focal le – McqOptions

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1.	Two thin lenses, one of focal length + 60 cm and the other of focal length -20 cm are put in contact. The combined focal length is [CPMT 1973, 89; BVP 2003]
A.	+ 15 cm
B.	-15 cm
C.	+ 30 cm
D.	-30 cm
Answer» E.

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