Index of refraction Definition and 161 Threads

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?

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...

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...

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!

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

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...

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.

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?

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...

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...

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...