A convex lens A of focal length 20 cm and a concave lens B of focal le – McqOptions

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1.	A convex lens A of focal length 20 cm and a concave lens B of focal length 5 cm are kept along the same axis with the distance d between them. If a parallel beam of light falling on A leaves B as a parallel beam, then distance d in cm will be [MNR 1990; IIT-JEE 1985]
A.	25
B.	15
C.	30
D.	50
Answer» C. 30

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