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Which focal length of a large convex lens is needed to project the image of a small electric bulb fixed on the wall of a room to the opposite wall, which is 3 meters away?

Options

  1. A1.5 m
  2. B2 m
  3. C0.75 m
  4. D4 m

Correct answer

C. 0.75 m

Step-by-step solution

Correct Option is : (C) 0.75 m

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