1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Refraction at a spherical surface

  1. Aug 14, 2009 #1
    1. The problem statement, all variables and given/known data

    attachment.php?attachmentid=20107&stc=1&d=1250245914.jpg

    2. Relevant equations



    3. The attempt at a solution

    I was kind of confuse with the use of refractive index.

    For the first part of question, n1 = 1.00 and n2 = 1.50. From what I know, the object is at vacuum so the n1 = 1.00.

    But why for the second part of the question, n1 = 1.50 and n2 = 1.00 ? After the first refracting surface, the image should be at the vacuum too. But why we use n1 = 1.50?
     

    Attached Files:

    • IMG.jpg
      IMG.jpg
      File size:
      72.2 KB
      Views:
      111
  2. jcsd
  3. Aug 14, 2009 #2

    tiny-tim

    User Avatar
    Science Advisor
    Homework Helper

    Welcome to PF!

    Hi stpmmaths! Welcome to PF! :smile:
    (I can't see your attachment yet, but …)

    I assume that the light starts by going into the sphere from the air (or vacuum), so it's going from n = 1 to n = 1.5;

    then it travels through the sphere (n = 1.5) until it hits the opposite surface and comes out again, so it's going from n = 1.5 to n = 1. :wink:
     
  4. Aug 14, 2009 #3
    Ok..I understand a bit.

    Now I came across with another question similar to this question(quite similar)

    Quenstion: attachment.php?attachmentid=20113&stc=1&d=1250304700.jpg
    Answer:
    attachment.php?attachmentid=20114&stc=1&d=1250304700.jpg

    Why the n1 is 1.50 if we say the light starts from vacuum?:confused:
     

    Attached Files:

  5. Aug 15, 2009 #4

    tiny-tim

    User Avatar
    Science Advisor
    Homework Helper

    Because the light starts from the coin, inside the sphere, not from vacuum. :wink:
     
  6. Aug 15, 2009 #5

    Redbelly98

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    Look carefully at the arrows in the figure. Where do they start from?

    EDIT: to clarify, look at the interface where the two rays meet. The ray arrows indicate they go from the glass into the air.

    p.s. Hello tiny-tim!
     
  7. Aug 15, 2009 #6
    Oo, I got it.
    Thanks everyone.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Refraction at a spherical surface
Loading...