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JAMB Physics 1993 Question 26

Question 26

Light and Reflection

Which of the following expressions gives the linear magnification produced by a concave mirror of radius of curvature r, if u and v are the object and image distances respectively?

  1. A.v/r − 1
  2. B.2v/r − 1
  3. C.u/r − 1
  4. D.2u/r − 1
Show the answer and explanation

Answer: B (2v/r − 1)

Explanation

m = v/u and 1/u = 1/f − 1/v, so m = v/f − 1. With f = r/2 this gives m = 2v/r − 1.