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At what angle does the light leave the glass?

  1. Mar 29, 2009 #1
    1. The problem statement, all variables and given/known data
    The drawing shows a rectangular block of glass (n = 1.52) surrounded by a liquid with n = 1.60. A ray of light is incident on the glass at point A with a 30.0° angle of incidence. At what angle does the ray leave the glass at point B?


    2. Relevant equations
    n1sintheta1 = n2sintheta2

    3. The attempt at a solution
    (1.52)sin(30) = (1.6)sintheta2
    theta2 = 28.359

    I have no idea what I did wrong.. should the angle be negative??
  2. jcsd
  3. Mar 29, 2009 #2


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    Homework Helper

    theta2 = 28.359
    This is the angle of refraction at point A. From that find the angle of incidence on the surface containing point B.
  4. Mar 29, 2009 #3
    Ohh, is this right then..?

    sintheta2 = (1.6) sin30/1
    theta2 = 53.13
  5. Mar 29, 2009 #4
    Nevermind, I got it :] 53.13 degrees is the answer. Thanks!
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