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Question: What is the combined focal length of a convex lens with a focal length of 30 cm in contact with a concave lens with a focal length of 20 cm?

Options

  1. A60 cm
  2. B50 cm
  3. C10 cm
  4. D-10 cm

Correct answer

A. 60 cm

Step-by-step solution

Correct Option is : (A) 60 cm

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