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Concave mirror

  1. Jan 29, 2009 #1
    1. The problem statement, all variables and given/known data
    An object whose height is 0.375 cm is at a distance of 10.5 cm from a spherical concave mirror. Its image is real and has a height of 1.145 cm. Calculate the radius of curvature of the mirror.

    Correct, computer gets: 1.58e+01 cm

    How far from the mirror is it necessary to place the above object in order to have a virtual image with a height of 1.145 cm?

    2. Relevant equations
    1/S + 1/Si = 2/R = 1/f
    Hi/H = -Si/S

    3. The attempt at a solution
    I am not sure how to relate the equations...Also, I am unsure as to how the image being virtual in the actual question changes things. I know f=R/2 = 7.9cm
    1. The problem statement, all variables and given/known data
  2. jcsd
  3. Jan 30, 2009 #2


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    Homework Helper

    Using Hi/H = -Si/S find S in terms of Si. Put it in the equation 1/S + 1/Si = 2/R = 1/f with proper sign of S, Si and f. Solve for S.
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