When a thin convex lens is put in contact with a thin concave lens of the same focal length (f), then the resultant combination has focal length equal toA. f/2B. 2fC. 0D. `oo`

When a thin convex lens is put in contact with a thin concave lens of

1.	When a thin convex lens is put in contact with a thin concave lens of the same focal length (f), then the resultant combination has focal length equal toA. f/2B. 2fC. 0D. `oo`
Answer» Correct Answer - D (d) Resultant combination of focal length, `F_(comb)=(f_(1)f_(2))/(f_(1)+f_(2))=(f(-f))/(f+(-f))=oo`

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When a thin convex lens is put in contact with a thin concave lens of the same focal length (f), then the resultant combination has focal length equal toA. f/2B. 2fC. 0D. `oo`

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