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A pin of small length ' a ' is placed along the axis of a concave mirror of focal length f , at the distance u (> f ) from its pole. The length of its image is ' b '. If the same object is placed perpendicular to its axis at the same distance u and the length of its image is now ' c ', then

Options

  1. Ab=a f^2 (u-f)^2
  2. Bc= a b
  3. Cc=b u-f f
  4. Dbc = a ^2 f ^3 ( u - f )^3

Correct answer

D. bc = a ^2 f ^3 ( u - f )^3

Step-by-step solution

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