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MHT CET202123 Sep 2021Morning ShiftPhysicsRay OpticsActual

The radii of curvature of both the surface of a convex lens of focal length ' f ' and focal power ' P ' are equal. One of the surfaces is made plane by grinding. The new focal length and focal power of the lens is respectively

Options

  1. A1 2 f , 2 P
  2. B2 f , P 2
  3. C2 f , P 2
  4. D2 f 3 , 2 3 P

Correct answer

B. 2 f , P 2

Step-by-step solution

aligned & P = 1 f =( -1) ( 1 R + 1 R )=( -1) 2 R & P ^ = 1 f ^ =( -1) 1 R & P ^ = P 2 and f ^ =2 f aligned

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