A convex lens and a concave lens, each havaing same focal length of 25 cm, are put in contact to from a combination of lenses. The power of the combination (in diopter) is

A convex lens and a concave lens, each havaing same focal length of 25

1.	A convex lens and a concave lens, each havaing same focal length of 25 cm, are put in contact to from a combination of lenses. The power of the combination (in diopter) is
Answer» zero 25 50 infinite Solution :`(1)/(F)=(1)/(f_(1))+(1)/(f_(2))=(1)/(+25)=0,P=(1)/(F)=0`

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A convex lens and a concave lens, each havaing same focal length of 25 cm, are put in contact to from a combination of lenses. The power of the combination (in diopter) is

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