Refractive index Definition and 280 Threads

First of all, sorry for bad english. Second of all sorry if such thread is already created, but I really need fast help.Homework Statement There's a lamp in the bottom of the lake. If you watch the lamp from the surface(out of the water) and your eyesight is crossed with the lake, you can see...

I get that the light changes speed as it enters a material with different densities, however I do not understand why a change in speed would cause a change in direction. For instance if I'm in a car and am going 55mph but slow down to 45mph I'm still going the same direction. It seems the only...

is it possible the refractive index remains constant while its extinction co-efficient rises as function of frequency? if yes when does this typical arise? i imagine that this can happen at the absorption edge of transmission spectra of a semiconductor but i don't find any explanation to this.

Snells law states that refractive index = (speed in medium 1)/(speed in medium 2) alternativley 1 μ2 = sin i / sin r Why therefore does Snells law also equal: μ1 * sin(angle-1) = μ2 * sin(angle-2) and for a critical angle μ1 sin C = μ2 sin 90 thanks

Dependence of refractive index on pressure Homework Statement Show that, in a gas (for which the refractive index is close to 1), the refractive index depends on the pressure as n_r = 1+ K\times p, and find the value of K. Homework Equations n_r = 1+ K\times p Clausius-Mossotti...

Dependence of refractive index on pressure Homework Statement Show that, in a gas (for which the refractive index is close to 1), the refractive index depends on the pressure as n_r = 1+ K\times p, and find the value of K. Homework Equations n_r = 1+ K\times p Clausius-Mossotti...

hi All, Just wondering how you get the complex refractive index of a material from relectivity measurements at a single angle. I understand you must infer some of the data, using the Kramers Kronig relations, is this right? Is there a direct way of calculating it? I see from an article on...

Sry for a proper wall of text, and it´s probably pretty "chatty" too, as I reason about things back and forth... Plz do feel free to comment on the reasoning since I post it to learn how to think about these things... I believe that I have sometime learned that one can relate refractive index...

1- what determines the refractive index of a material? i understand that it is ratio between velocities in vacuum and medium but i want to know about complex refractive index which also accompanies extinction co-efficient. my explanation is that bent and slowing down of light depends on crystal...

I'm probably doing something stupid here... A wave travels from a medium into a second medium with a smaller refractive index. By definition the speed of the wave increases. Then lambda*f = v, so the wavelength also increases. According to de Broglie, this means the momentum goes down...

Hi, I have an organic chemistry assignment identifying an unknown sample. My tutor has asked for the properties (I can find all but refractive index) for vanillin and p-bromobenzophenone. I found that for Vanillin it is 1.555 but I know that it changes with temperature and I cannot find a...

Maxwell theory n=\sqrt{\epsilon_r \mu_r Refractive index for water is n=1,33. For water \epsilon_r=81, \mu_r=1 so it should be n=9 Why we have so big anomaly for water?

Homework Statement Define refractive index in terms of changes in the velocity of a wave in passing from one medium to another. Homework Equations The Attempt at a Solution Would I be right in saying that in terms of the question above, refractive index is the constant found between the...

Homework Statement A ray of light is incident in water on a plane water-glass boundary. The angle of incidence is 30 degrees. Calculate the angle of refraction. (Refractive index of glass with respect to air =3/2, refractive index of water with respect to air = 4/3). Homework Equations...

I'm thinking of normal dispersion, of course, far from any resonances, say in bk5 glass or water. I thought it might be due to higher-frequency light undergoing more collisions, but I'm not sure. Thanks!

Homework Statement A light beam incident on a glass slide at an angle of 60 ˚, being partly reflected and partly refracted. It notes that reflected and refracted beams are each at 90 ˚ What is the refractive index of glass? Homework Equations n1sinσ1 = n2sinσ2 The Attempt at a...

Homework Statement My question is very basic, yet one which has become increasingly frustrating. I am doing an investigation into determing the refractive index of Perspex for an assignment. To do this I am using a light ray box to shine a ray onto a rectangular perspex prism, and then using...

Hi I'm trying to sort this concept out in my head and have reached a stumbling block! 1. ok so light travels through medium a and transmits through medium b and refracts. The angle or refraction is given by snell's law, and quantified by the refractive index of materials a and b. 2. But I...

Homework Statement I uploaded the question below.2. The attempt at a solution At first what I did was using the Snell's Law formula n_1 \sin{\theta _1}=n_2 \sin{\theta _2} then I did this, n\sin{\ 45}=1 \sin{\ 90} so this is the minimum value that I got n=1.41 I'm not sure if my answer is...

If a beam of light enters water from air at 30 degrees from the normal. It then enters a glass block and exit into air. At what angle does it exit from glass to air ? My friend says it exist again at 30 degrees to normal. The refractive index of water is 1.3 and glass is 1.5.

When I was a little kid, I met a gemologist who showed me a cool trick with a ring he'd bought for his wife. When he submerged it in water, the crystal disappeared! As I now know, this crystal had an index of refraction of 1.33. Anyone know what this crystal is and/or how I can get my...

as described in the title, what's the relationship between these 2 quantities in a given material? ty

A ray of light strikes a square glass block at an angle of 45 degrees and enters the glass. If this block is surrounded by air (n=1), what is the minimum value of the refractive index of the glass if the total internal reflection occurs at point P. (see attached diagram) I'm really lost on...

Homework Statement A beam of light is split into two coherent beams of intensity I which are in phase. The two beams are sent through different paths and superimposed at the same spot on a screen. A path difference is to be achieved by inserting a glass window of refractive index of 1.7 in the...

I am trying to understand the relation between transparency and refraction index. Searched this forum so found and read some topics too. As I undertand, transparency is related with atomic structure and phonons. This is ok. If light beam (or say photons) faraway from phonons (and atoms), they...

can some one tell me how the refractive index changes with the wave length of the light?

Optics, prism and angle of deviation 1. Angle of incidence, emergence and deviation are respectively 30, 60 and 45 degree. 2. 3. I think that it is irrespective of the refractive index.

Building Materials Refractive Index?? Hi all, does anybody know the refractive indices of these materials (used in houses)? - Wall bricks - Wood (used in doors) - Glass - Plastic - Concrete (in ceiling and floor) and any other common materials :) thanks in advance

refractive index... snell's law... help! Hi, im having a LOT of trouble with what seems like a basic question. i have been stressing over this for nearly 3 hours now. can anyone help me out? here it is: Light propagating from water into air is incident on the water surface at the angle of...

I am currently undergoing advanced higher physics and my investigation is on measuring refractive index. I have conducted 3 experiments so far: the standard ray lamp experiment from higher and two different versions of the apparent depth method. However, these experiments have been simple and...

In physics class we did an experiment where we dropped a metal pin in a beaker of water, covered half the beaker with a mirror and clamped another metal pin above the beaker. We had to find the refractive index of the water by measuring the apparent depth of the submerged pin and dividing it...

Homework Statement We learn from school that when we shine white light through a prism, dispersion occurs. This is because the light of varying wavelengths are refracted to a different extent due to how refractive index varies with the wavelength of light. So why does refractive index vary...

There doesn't seem to be any difference between n = (1-\delta) - i\beta (the refractive index in the x-ray regime, where 1-\delta is the real part and \beta is the the absorption index) and n^{\ast} = n - ik (the complex refractive index, where n is the refractive index and k is the...

I was wondering how close 2 refractive Indexes have to be in order to be not visible? I currently have a glass fiber at 1.521 and am researching resin systems to match and so far have 2 - one at 1.506 and the other at 1.4736. I know which one is better (1.506), but is it close enough to...

in relating the index of refraction to the relative permittivity (dielectric constant/function). it is known that n = \sqrt{\epsilon_r} for optical frequencies (i.e. \mu_r=1. now this website http://hyperphysics.phy-astr.gsu.edu/Hbase/tables/diel.html#c1 gives the relative permittivity of...

for an example, polycrystalline silver, its index is n=0.135 and k =3.999 at the wavelength of 633nm, what does the nk mean, is that telling us the wavelength in the silver equals 633/0.135 nm ? and how to calculate the refractive angle in the metal? Give a good explanation, please.

Hi folks, Does anyone have a good reference for the refractive index of the near surface Martian atmosphere? (Or alternatively, the means to estimate it from readily available data!) I'm struggling to think of an equation for which I've got enough of the variables to be of use, (for...

Homework Statement The diagrams below illustrate the formation of a rainbow. Figure 1 shows the general arrangement and Figure 2 shows the path of a ray through a raindrop with the centre of the raindrop is labelled O. Figure 1: Figure 2: a.) Where the ray enters the raindrop in...

Homework Statement A slab of glass has a refractive index of 1.3. What will be the speed of light in this glass? Homework Equations The Attempt at a Solution \frac{sin i}{sin r}=1.3 ?

Does anyone have an idea about a formula relating the refractive index of a medium to the temperature gradient (Generally)?

?? Refractive Index ?? Dear all, For particle size distribution of MoS2 I need refractive index and absorption for this compound. Actually I couldn’t find it in the literature. Could you help me for this aim?

hello everyone Consider extinction coefficient k, n becomes N=n-ik. the textbook says NsinA=N'sinB still holds itself. But the sinB,for exmple, may be a complex number, i want to know how to get B? how to understand this situation, which is the refractive angle? the B's real part?

Refractive Index Units - URGENT - Homework Statement Does the Refractive Index of a medium have units. If so what are they? i am needing this for a lab report - so i can quote answers and feel fine that i am not giving any units. I am pretty sure there arent any.

http://aycu12.webshots.com/image/44931/2004851894362651280_rs.jpgany idea what then?

why some materials have bigger refractive index than others? Let's say why air have 1.003 refractive index, and quartz glass 1.46?

How can one measure refractive index by knowing the change in angular range of the first dark bands of an interference pattern(single slit diffraction), when the apparatus is change from air to under water? I think I missed that lecture, and I am still catching up.

Homework Statement For substance X, the refractive index is nx. For another substance Y the refractive index ny. Show that the refractive index for light passing from x to y is nx/ ny. 2. The attempt at a solution I'm finding it difficult to devise a solution, but I think the answer...

Refractive Index Problem invloving prism (Please Help) Homework Statement What is given is a prism, angle of deviation and apex angle, I also have to find refractive index of the prism. To solve the problem I must prove that: Nprism = sin((A+d)/2)/ sin(A/2) The diagram given of the...

Hi, I recently read about the exciting research and progress being made with lenses made from negative refractive index materials. In theory, these materials have no limit to their resolving power and so far experiments have shown they can image objects smaller than that possible using...

I'm looking for Methanol (CH3OH) refractive index (n,k) table in Infra Red 2-10micron If anyone can help me with that