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A convex lens makes a real image 4 cm long on a screen. When the lens is shifted to a new position without disturbing the object, we again get a real image on the screen which is 16 cm tall. The length of the object must be

Physics-General

  1. 8 cm    
  2. 12 cm    
  3. 20 cm    
  4. 1 fourth cm
       

    Answer:The correct answer is: 8 cmO equals square root of I subscript 1 end subscript I subscript 2 end subscript end root equals square root of 4 cross times 16 end root equals 8 c m

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