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What is the focal length of the convex lens used in this scenario where an object placed 90cm away from it forms an image at two different locations separated by 20cm?

Options

  1. A21.4 cm
  2. B90 cm
  3. C110 cm
  4. D70 cm

Correct answer

A. 21.4 cm

Step-by-step solution

Correct Option is : (A) 21.4 cm

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