Index Definition and 795 Threads

I'm having a problem getting my graph labels to work. I get an error saying "? Index exceeds matrix dimensions. Error in ==> aeroproject2 at 88 plot(alphaLzero-8:alphaLzero+8,CL(1,1:17)),title('CL vs Alpha'),xlabel('Angle of Attack'),ylabel('CL')" can anyone help...

Well, this is awkward. I seem to have forgotten what star has a 0.0 value in the V-I color index. I almost want to say Vega but that's the 0.0 in the B-V color index. I also seem unable to find raw data for the V-I color index values for spiral galaxies and was wondering if someone would...

This is a brief tutorial to cover the basics of index notation which are useful when handling complicated expressions involving cross and dot products. I will skip over a lot of technicalities (such as covariant and contravariant vectors) and focus on 3 dimensions - but all of what I say here...

A scientist notices that an oil slick floating on water when viewed from above has many different rainbow colors reflecting off the surface. She aims a spectrometer at a particular spot and measures the wavelength to be 750 nm (in air). The index of refraction of water is 1.33. The index of...

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

(I'm still reading the QED book by Feynman...) What property of the material causes a specific refractive index for a particular medium? (in other words, from the FAQ section by ZapperZ, "So the lattice does not absorb this photon and it is re-emitted but with a very slight delay.". How is...

Hi, this is the question in my homework. Explain what happens when a light ray enters and leaves a glass block if it hits the face of the block at right angles to it. Can someone pelase help me, i think that the light ray would just go straight through the block without bending but I am...

I have found the relativistic mechanical index of refraction which I think is n = \sqrt{[( E - V + mc^{2})^{2}- (mc^{2})^{2}]/[( E + mc^{2})^{2}- (mc^{2})^{2}] Follow the same procedure as this thread https://www.physicsforums.com/showthread.php?t=176081&highlight=optico-mechanical...

The index of refraction is a complex number if the mediums conductivity is non zero. n=Re(n)+Im(n)*i We know that for real refractive index: v=c/n How is the corresponding relation for complex n? I would expect (and got from my calculations) v=c/Re(n), but since Re(n) may...

Normal glasses have a larger refractive index for blue than for red. Are there special glasses that differ in this respect? Or maybe are there some minerals that behave differently, still being transparent in the visible spectrum and colorless? Thanks to tell me if you know something about...

I have sustained the worst injury known to geekhood. I have cut the end of my right index finger. Mouse-clicking has become a monumental task, comparable to scaling everest. :mad::mad::cry::cry::mad::mad:

As is demonstrated by research (http://en.wikipedia.org/wiki/Calorie_restriction#Intermittent_fasting_as_an_alternative_approach) , intermittent fasting produces similar results to calorie restriction. However, I have a question here. Are the result of intermittent fasting dependent on the...

light refractions problem I don't even know where to start with this problem. Can someone please help me out? As shown in Figure P22.49, a light ray is incident normal to on one face of a 30°-60°-90° block of zircon(n= 1.923) that is immersed in water. Figure P22.49 (a) Determine the...

I was reading this article http://news.bbc.co.uk/2/hi/science/nature/841690.stm I don't understand how this doesn't defie relativity. It sais something about you can see the light exit the caesium before it even enters, thus having went faster then the speed of light but the article sais it...

I would like to hear a second opinion about this solution that was presented to us. As a background, we have a system that will compute for the total number of records for a given a file. The arrival time for each file is set for 5 minutes. For monitoring purposes, the problem now is how to...

Homework Statement Determine a and b such that A is nipotent of index 2. A:= <<a,b>|<0,0>> A is a 2x2 matrix column 1 is a and b , column 2 is 0's Homework Equations A^k=0 to be nilpotent and to be nipotent it has to be that A^(k-1) doesn't equal 0.. The Attempt at a...

The Maxwell's relation in electromagnetic theory states that refractive index is equal to the square root over the di-electric constant. This relation holds for some simple gases.But more generally,it does not.My question is why this is the case. Eugene Hecht says that this is because n...

Homework Statement Suppose a convex lens is ground so that one surface has a radius of curvature of 30.0 cm and the opposing surface has a radius of curvature of 40.0 cm. The focal length is 34.2cm. What is the index of refraction of the lens? What kind of glass is the lens? Homework...

Suppose a convex lens is ground so that one surface has a radius of curvature of 30.0 cm and the opposing surface has a radius of curvature of 40.0 cm. The focal length is 34.2cm. What is the index of refraction of the lens? What kind of glass is the lens? Need help by using the formula...

can you please explain some of these questions to me? Thanks. In the PR book, it defines vacuum as empty space and I don't really know what that means. Does it mean that there is nothing (no air molecules, no other gasses, etc.) in that space? (is the atmosphere of space a vacuum also?) I've...

How close do two refractive indices, e.g. a liquid and solid, have to be for the solid in the liquid to be invisible to the naked eye? 1st decimal place, 2nd decimal place?

Is there a general formula to calculate the refractive index of a mixture of two liquids of known refractive index, e.g. water and ethanol, or water and glycerol?

Hello I'm trying to solve a problem where I'm asked to find the optimum index of refraction for an antireflective coating on a piece of glass. In trying to derive an equation for it I keep coming across this in the internet (where 1,0, and s should be subscripts) n1=sqrt(n0ns) where n1 is...

I'm puzzled (as usual). The Kramers Kronig transform is commonly used to relate real and imaginary components of the electric susceptibility- \chi(\omega) It appears from reading papers that it also works for relating real and imaginary components of the refractive index. But why? That...

How does one measure the index of refraction of a liquid, more specifically the angle of refraction? I'm finding it's relationship to temperature. I can't just dip the protractor into the liquid( as a test medium I used water compared to air) and measure the angle that is in the water(either...

A professor of mine recently remarked that dirac notation is easily the best in physics & we'd quickly realize this once we take a course in relativity. I've already taken the course & I find myself disagreeing with him, but maybe that's only because I enjoy relativity more. Curious what you...

Ok, so semi-irrelevant information out of the way first - I'm writing a program that will give a basic model of the solar system - taking into account interactions from the planets on each other. I can get my program running when containing the individual starting points of each of the...

Hi, I am using a Matlab program called f2matlab, which converts fortran 90 code to MATLAB code. But I keep on getting the following error: Attempted to access temp3(1); index out of bounds because numel(temp3)=0. Does anyone know what this error relates to? :rolleyes: Thanks in...

This article is as good as any tutorial on the physics of negative index of refraction. It was co-written by John Pendry, who has been credited for inventing/discovering the metamaterial that exhibits this property.Zz.

Hi There, Ok, I'm new to this so I'm sorry if this is abit warbled!... We have a normal subgroup N of a finite group H such that [H:N]=2 We have a chatacter Chi belonging to the irreducible characters of H, Irr(H) , which is zero on H\N. I have already shown that Chi restricted to N =...

http://math.ucr.edu/home/baez/crackpot.html Doesnt point number 37 hint at string theory by what the likes of smolin and woit says? And btw, I am no expert in this and I announce that all i have read is a few "layman" books and have no heck of idea what string theory actually is and my...

The problem is described here: http://phstudy.technion.ac.il/~wn117066/Problems2.pdf In question 1 I need to find the refractive indices for both polarizations at 760nm. I'm not quite sure how to go about this - which model of dispersion best fits Calomel? (I'm done with the exercise...

For instance, how would a "gem" made of negative refraction index material appear next to a diamond?

In my struggles to understand index notation, I am trying to figure out how my book came up with the following transformation. \frac {D \omega}{Dt} \cdot \omega = \omega_j \partial_j v_i \cdot \omega + \nu \partial_j \partial_j \omega_i \cdot \omega = \frac {D \frac{\omega^2}{2}}{Dt} =...

I am playing around with learning index notation for tensors, and I came across the following where C is a 0th order tensor: E_{ijk} \partial_j \partial_k C = 0 I believe this equates to \nabla \times \nabla C. I don't understand why this comes out to 0. Any ideas? Also, I am trying...

is there a site with this? i want to see how the ref. index. of a soln of glucose varies with concentration. can someone tell me if my prediction that as concentration increase, ref. index increases is correct?

Hi I have just conducted the experimental stage of a practical 'to find the refractive index of different objects using Snell’s law' (which states sine i/sine r =N). The objects chosen were Ice, Glass, and Perspex. As 3 trials were taken for all 3 objects, if these points were graphed, and a...

I was asked the write down the Miller indices for a plane. The question is further described in http://www.wretch.cc/album/show.php?i=kenmse&b=13&f=1643363273&p=2 I took point A as an origin. For the plane "opn", the intersections with X axis and Y axis are a/2 and -a respectively. Then I...

I am doing my homework and i come across a question. What is the SI unit for refractive index?All my revision books did not have the answer.Or perhaps the book is wrong by any chance?

This is from my Physics practical experiments. The experiment is to find the refractive power of the prism for different colours and also to determine the dispersive power of the material of the prism. My question is how does the refractive index of the material of the prism vary with the...

hi i've got to do measure hte refractive index of a liquid with mirror and lens first of all how can i measure hte refractive index of air in this way? i don't get how i can do this, please explain :| and then for the liquid, I've been told to put the liquid over the mirror and then the...

I have a problem with an inequality. In the numberator of one term I have X sub k, and in the denominator I have the sum X sub ks from 1 to n. So let's say I use n=2 and have two terms in the denominator Xsub1 and Xsub2. What am I using for the X sub k in the numerator. It definitely is not X sub n.

The only definition of a free group I have is this: If F is a free group then it must have a subgroup in which every element of F can be written in a unique way as a product of finitely many elements of S and their inverses. Now, is it possible to form a commutator subgroup of F? That is...

"An electromagnetic radiation has a frequency of 5 x 10^14Hz a) (wave in vacuum = 600nm) b) (wave in water = 440 nm) c) what is the index of refraction of a medium in which the speed of this radiation is 2.54 x 10^8 m/s?" so given: c = 2.54 x 10^8 m/s f = 5 x 10^14Hz...

I want to measure the refractive index of a thin cantilever ; however the sample is too small (about tens of microns). on the other hand, the cantilever maybe not flat at all and it is curly. how can I do it?

I can't seem to figure these out guys...maybe I'm missing a few equations too. 1. If light of wavelength 600nm in air enters a medium with index of refraction 1.50, its wavelength in this new medium is... A. unchanged B. 900nm C. 400nm D. 602nm ---I know that n=c/v...but I don't...

We know,n=(rel.permittivityxrel.permeability)^(1/2) For natural transperant mediums (to visible light of EM spectrum)are non-magnetic.So, rel.permeability=1 hence n=(dielectric constant)^(1/2)...

Here is the question: A factory uses a beam of light to allow workers to visually check the temperature of a liquid. A semi-circular crown glass (refractive index (n) =1.75) block is placed in a liquid X whose refractive index n changes with temperature T (in °C) according to the formula: n =...

Let n denote the refractive index of water. What fraction of the speed of the light in air is the speed of underwater light? Let \theta denote the critical angle for light going from water to air. Find the value of sin \theta.

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...