Index Definition and 795 Threads

When constructing a Rayleigh Refractometer the formula for the refractive index of a gas at pressure P and temperature T is: mu(P,T) - 1 = (gamma) P/T where, mu(P,T) = refractive index as a function of pressure and temperature and gamma = [n(lambda)Ta]/[L(deltaP)] where, n = fringe...

Can someone please help me out? I was wondering whether or not there is a solid (i'm thinking a form of silicon) That is transparent and when an electric charge of some kind is passed through it it's refractive index changes There was an article in new scientist about this along time ago...

Hey , I need some indication to solve this problem: A ray light impinges at a 60 degres angle of incidence on a glass pane of thickness 5mm and index of refraction of 1.54. the ligth is reflected by a mirror that touches the back of the pane. By how much is the beam displaced compared with...

How would i go about solving the problem of for which values of a is the congruence ax^4≡2(mod 13) solvable? I think it might have something to do with power residues but I'm not sure. Thanks

I can't seem to get these power series to match up so that I can solve the equation...heres my work:

Wkipedia gives refractive index n^2 = (Relative Permittivity) x (Relative Permeability) but taking water as an example n = 1.33 Relative Permeability = 1.0 (roughly) Relative Permittivity = 80.4 1.33^2 = 1.77 Which is NOT 80.4 what's wrong?

Given any index of refraction, how would I find a wavelength in that medium? Should I use frequency= c/wavelength? For example, if a piece of glass (medium) has a index of refraction 1.12, what's the wavelength?

Just to clear things up... does a greater index of refraction mean that the light bends more or less?

Dear all, i am a bit confused with a very simple equation connecting refractive index of water and its dielectric constant for visible range of wavelengths and room temperature. i hope, You can help me as we know, the refractive index 'n' can be defined as n=sqrt(epsilon*mu)...

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...

Ok I'm giving these another go. I found the following DE from a reduction of order problem and figured that it would be an alright question if I turned it into one requiring a series solution. However I'm stuck. I think it's just a matter of index shifts to get an appropriate recurrence relation...

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!

Given U^k_i, the components of U is a delta function i.e for i=k U^i_k =1, to prove it is invariant under Lorentz transformation~~ I don't know how to express it in Einstein summation notation, I am very confused with the upper-lower index, is it right to write the transformation in this...

http://math.ucr.edu/home/baez/crackpot.html :smile: :smile: :smile:

Can anyone show me a proof of "refractive index= (real depth)\(apparent depth) "? I found the proof in my book has a mistakes and I found some contradicts to this equation.

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

I need to determine the refracting index of a thin piece of plexiglas. Is there a way to find the index exactly?

I've been stuck with this problem since a while.. thought I'd ask here; \nabla \times \dfrac{\vec{A} \times \vec{r}}{2} solving normally isn't any problem, but I have to do it with index notation, where A is an arbitrary vector field and r is the position vector) This is how far I can...

im having trouble setting my TI-83 Plus into "degree mode" so i can't seem to get the answers for these problems...im probably doing them wrong too A material has an index of refraction of 1.75. What is the critical angle for this material? Sin(critical angle)=1/n, n being the index of...

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...

Hello, I'm a bit stumped on a problem and wondered if anyone knew how to approach this problem: When a Newton's ring apparatus, ( Fig. 24-30(see attached) ) is immersed in a liquid, the diameter of the eighth dark ring decreases from 2.99 cm to 2.49 cm. What is the refractive index of the...

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.

Does anybody know how to find how often a specific researcher is cited in leading journals? Is such statistics kept in some way at all?

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?

What are the properties of materials havind negative refractive index? Are they theoretical or do they exist?

ok I've been wondering about this for awhile when people say the speed of light slows down when going through an object (ie glass). does the speed of light actually slow down to 2x10^8 m/s or does the speed of light actually stay constant at 3x10^8, but the photons collide with the SiO...

Is the following equation which relates to light refraction index and the amount which bounces back been proven experimental or theoretically(mathematicaly)? R = [(n1-n2)/(n1+n2)]

The equation relating these is : sine(critical angle) = refractive index between 2 meterials. Could someone please supply a proof for this? Also, as a side question :wink: , is there a proof for the sin i / sin r = v1/ v2 , not including the one in which you draw triangles and...

Negative Refractive index! Is negative refractive index possible(theoretically,in optics). If so what are its implications? :smile:

Hello, all, I am here is to ask how can I factorise an equation with fraction indeces?? (Help~) The question I have got is x^(3/2) + a^(3/2), and the suggested method is using the factor theorem... but I just don't understand how could that works... However, I would be very grateful if...

Light ray goes into a container at 70 degrees, the container is made of perspects. The refective index of perspex is 1.48. What are the angles of refraction in (i) the water; (ii) the plastic, (iii) the air below the tank. I can't work it out, the answer to the first bit is 26 degrees, i...

hello, i just started learning index notation in my engineering class, and I am having some trouble. one of the problems on my homework was: putting this in index notation: \vec{f}=g \frac{m_1m_2}{\vec{r}^2} \ \frac{\vec{r}}{\sqrt{\vec{r}^2}} and then another problem that reads...

I have a transparent silicone model flow chamber which I would like to use for flow visualisation studies. Ideally I would like a fluid whose refractive index is the same as the silicone, hence minimising distortion of the field of view. The refractive index of the silicone model is approx 1.4...

Does anybody here know the refraction index of paper? I couldn't find any info on this... Any kind will do.

The Question: A 45-45-90 prism is immersed in water. What is the minimum index or fefraction the prism must have if it is to reflect totally a ray incident normally on one of its faces. Now, we have found this question a bit hard to understand. We assume that light is hitting one of the...

Hi, I don't understand this problem at all: Rewrite the following sum with the index of summation starting at 3 in summation notation: \sum_{i=1}^{6}(5+3i) I know that the sum is 93 but I'm not sure what to do... Thanks for the help!

Hello, will refreactoin index of water or any material will change its refreaction index when temperature changes? What make the speed of light slower in air compare to vacum.

How we can calculate the Miller's index? :smile: Thanks

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...

How do u figure out the ratio of the refraction index if you have to unknown materials, that of which, one is 1.25 greater than the speed of sound.

im sick of logs use base and index steps to show the answer to 37 x 0.785 using logarithms with a base of 10, e and 5. i just want to know how to start this problem. thanks in advance