Index of refraction Definition and 161 Threads

  1. D

    Why Is a Complex Index of Refraction Necessary?

    Why would one need to use a complex index of refraction? Are there circumstances in which the ordinary index of refraction breaks down? What are they?
  2. O

    Find Speed of Light in Medium with Index of Refraction

    I am having a little bit of trouble finding the speed of light in a given medium when you are only supplied with the index of refraction. For example, I was given that n=1.36 in ethanol, and I had to find the speed of sound in ethanol. I know the equation for the index of refraction is n=c/v...
  3. L

    Spherical glass object with index of refraction N

    imagine there is a spherical glass object with index of refraction N is that possible that for some N and angle of incidence A, the light will be total internal reflected forever. In other word, the light will travel within the object forever? i have been trying to proof it. but i don't know...
  4. E

    Can the index of refraction of a substance be altered by an external action?

    Hi guys. I'm doing this science fair project and I needed to know if there is a substance (any substance!) whose index of refraction can be changed/regulated by applying an electric current (or any other action) to it. I appreciate all help. Thanks!
  5. C

    Discovering the Index of Refraction: A Quick and Easy Guide"

    my brain is fried...and I need help again. How do I find the index of refraction again??
  6. S

    How Do You Calculate Phase and Group Velocity from Refractive Index Data?

    given is a graph of n(lambda) vs lambda where n is the index of refraction N(1000) =1.45 Estimate Vphase and group velocity using the above info. i know that n = \frac{c}{v_{\phi}} = \frac{ck}{\omega} i can't simply susbtitute into that above relation because the lambda given is that...
  7. F

    Index of Refraction: Proving Rays Are Parallel

    I have input rays into a glass plate and output rays for this glass plate also. How can I prove that they are indeed parallel. I'm thinking all I need to do is extend the inout and output rays, and indicate that they are both 180 deg. Visually, they will appear parallel anyways.
  8. S

    Dielectric constant and index of refraction

    I'm a little confused. My source says the dielectric constant for water is 80. Then I have the equation that gives the index of refraction as n=\sqrt{\epsilon_r} (since it isn't very magnetic). But the index of refraction for water is 1.33. What am I missing?
  9. D

    Index of refraction of the plexyglass

    If Sin(theta r)/Sin(theta i) is reversed from Sin(theta i)/Sin(theta r) = n, what does this mean? I'm quite confused since I'm doing a physics lab, and the class was told to make a graph where we measured angles with polar paper, pins and plexyglass. Could it possibly the index of refraction...
  10. C

    Calculate Index of Refraction: Air to Glass

    In this figure the path of the light passes from air to glass. Calculate the index of refraction n1 = air = 1 n2 = glass = ? Sin theta 1 = 30degrees sin theat 2 is = 20 degrees formula used n2 = n1*sin theta 1 / sin theta 2 sin of 30/ sin of 20 = n2 = 1.46 is this correct hope the...
  11. M

    Calculating the index of refraction of a gas

    Question: One of the beams of an interferometer, as seen in the figure below, passes through a small glass container containing a cavity D = 1.40 cm deep. When a gas is allowed to slowly fill the container, a total of 230 dark fringes are counted to move past a reference line. The light used...
Back
Top