An object is placed first at infinity and then at 20 cm from the objec – McqOptions

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1.	An object is placed first at infinity and then at 20 cm from the object side focal plane of the convex lens. The two images thus formed are 5 cm apart. The focal length of the lens is [SCRA 1994]
A.	5 cm
B.	10 cm
C.	15 cm
D.	20 cm
Answer» C. 15 cm

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