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Homework Help: Angular magnification

  1. Feb 7, 2010 #1
    1. The problem statement, all variables and given/known data
    Conside two ways to use a convex lens (1) image formed at infinity s'=-[tex]\infty[/tex] and (2)s' at the near-point s'=-p_n. The angular magnifications are M_[tex]\infty[/tex] and M_pn respectively.
    Derive the angular magnification M_pn and show that M_pn = M_[tex]\infty[/tex] + 1


    2. Relevant equations
    M_angular = [tex]\stackrel{\theta '}{\theta}[/tex]


    3. The attempt at a solution

    I found the object distance for (2) to be [tex]\stackrel{fp_n}{f+p_n}[/tex]

    M_pn =[tex]\stackrel{y/s}{y/p_n}[/tex] =p_n /s = [tex]\stackrel{f+p_n}{f}[/tex]

    M_[tex]\infty[/tex] = [tex]\stackrel{y/f}{y/p_n}[/tex] =[tex]\stackrel{p_n}{f}[/tex]

    so M_[tex]\infty[/tex] +1 = [tex]\stackrel{p_n + f}{f}[/tex] =M_pn

    so it worked out, but im unsure whether i put in [tex]\theta[/tex]' and[tex]\theta[/tex] correctly for each case, as i didnt really understand what i was doing.
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
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