Question:medium

A convex lens of focal length 20 cm is in contact with a concave lens of focal length 40 cm. The power of the combination is:

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Always use SI units (meters) for focal length when calculating Power in Diopters.
Updated On: Apr 8, 2026
  • +2.5 D
  • -2.5 D
  • +5.0 D
  • -5.0 D
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The Correct Option is A

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