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A converging lens of focal length 40 cm is fixed at 40 cm in front of a screen. An object placed 120 cm from the fixed lens is required to be focused on the screen by introducing another identical lens in between. The second lens should be placed at a distance x from the object where x is

Options

  1. A40 cm.
  2. B50 cm.
  3. C140 cm.
  4. D150 cm.

Correct answer

C. 140 cm.

Step-by-step solution

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