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Two identical lenses made of the same material of refractive index 1.5 have the focal length 12 cm . These lenses are kept in contact and immersed in a liquid of refractive index 1.35. The combination behaves as

Options

  1. Aconvex lens of focal length 27 cm.
  2. Bconcave lens of focal length 6 cm .
  3. Cconvex lens of focal length 9 cm.
  4. Dconvex lens of focal length 6 cm .

Correct answer

A. convex lens of focal length 27 cm.

Step-by-step solution

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