Reflection Definition and 917 Threads

Homework Statement Part(a): Show relation between impedance of dielectric and impedance of material: Part (b): Show the ratio between reflected and incident amplitude is: Part (c): Three layers now from left: vacuum, dielectric 2 sandwiched inbetween, and dielectric 1. Part (d)...

hi all, i have wrote codes for 2d fdtd in different permittivity (epsilon). in this code, cell size is 200 x 200, start with eps=1 from center, and different permittivity started at boundary (i1,i2) = (25,75) = (j1,j2), epsilon = 2. the problem is, when the wave propagates and approach...

Electric field of an electromagnetic wave incident on a metal accelerates free electrons, and these accelerating electrons then emit radiation opposite to the electric field of the wave, thus reducing the resultant amplitude in the forward direction. Radiation emitted in the backward direction...

I have been reading the explanation of reflection that Feynman provides in The strange theory of light and matter. There are two things I do not understand: a) How does he choose the directions of the little arrows below the diagram? I understand that each path is different in that it...

In x-ray diffraction , even though its reflection is happening , we call this as x ray diffraction. why is it so?? i don't know whether it has been discussed previously here.

Homework Statement Hi! I'm having a problem with one assignment and I would really need som help. The question is: The Chandra X-ray telescope is used for observations in the 0.1-10 keV range. Focal length is 10 m, max mirror radius is 0.6 m. What is the largest reflection angle in the...

why does a change in impedance causes reflection? I know that R=(Z2-Z1)/(Z1+Z2), but what is it that makes the wave be reflected? thanks

Hi! I'm having a problem with one assignment and I would really need som help. The question is: The Chandra X-ray telescope is used for observations in the 0.1-10 keV range. Focal length is 10 m, max mirror radius is 0.6 m. What is the largest reflection angle in the optics (assuming...

It is well known that the evolution of the input reflection coefficient, ρ, of a LTI causal passive system with frequency, f, always presents a local clockwise rotation when plotted in cartesian axes (Re(ρ), Im(ρ)), e.g. in a Smith chart, as shown in the attached figure. It must appointed that...

I want to apologize first of i post at the wrong section, not very sure if this is the right place for this post. First question, does the photon get absorbed when it hit highly reflecting material like mirror ? What make them look so different from the other transparent object? And I just...

f(-x) is a reflection over the y axis -f(x) is a reflection over the x axis Now, how do we represent a reflection over y=x?

Hello everyone, Here is something I've discussed with some colleagues recently and that generated a lot of disagreement, so I wanted to bring the topic to Physics Forums to ask what is your understanding of the situations and wheter you agree with the "solution" I provide below or not. Imagine...

Homework Statement Red light is incident in air on a 30o - 60o - 90 o prism as shown. The incident beam is directed at an angle of φ1 = 37.6o with respect to the horizontal and enters the prism at a height h = 26 cm above the base. The beam leaves the prism to the air at a distance d =...

Homework Statement Finding lightpaths with given starting and ending points via one or more mirrors. In those kind of problems you try image someone pointing a laser with a very narrow beam at a certain direction to the mirror, so it will reach point B. For example: You are seeing a square...

a mirror reflection Homework Statement Create a set-up, as shown in the Figure, consisting of two mirror tiles (A and B) and a bird face, facing to the right . Make sure the two mirrors are perpendicular to the table and parallel to each other. The situation shown is a front view of the...

Consider snell's law n_1 \sin{\theta_1}=n_2 \sin{\theta_2} ( n_1 and n_2 are real). We know that if n_2<n_1 , there exists an incident angle called critical angle that gives a refraction angle of ninety degrees i.e. \sin{\theta_c}=\frac{n_2}{n_1} . But if the incident angle is greater...

Hi And Need Help The main Question is what happens to light and cause go into next medium as total internal reflection happens for incident angles higher than critical angle ? so the main question is why the light path throughout the second medium? We know when light travels from a medium...

Hi, I'm confused about reflection and absorption in materials. Is glossiness of an object determined by roughness of its surface rather than its inability to absorb visible light? If there are dark-colored objects where one has a matte finish and the other has a glossy finish, does this mean...

Can anyone please provide an intuitive explanation of why phase shift of 180 degrees occurs in the Electric Field of a EM wave,when reflected from an optically denser medium and also why the phase remains same on reflection from a denser to rarer medium? please try to explain on an atomic/sub...

Homework Statement An optical fiber consists of a glass core (index of refraction n1) surrounded by a coating (index of refration n2<n1). Suppose a beam of light enters the fiber from air at an angle θ with the fiber axis as shown in attached. (a) Show that the greatest possible value of θ...

I have seen discussions which suggests that there is no solution for the interval after the step in a step potential where E = V0. The set up is a potential step where E = V0, with an interval 1 defined as x < 0 before the step and an interval 2 as x > 0 after the step. Is the following...

Hello, this is my first post to this site. I had this idea a few nights ago, and I've been trying to wrap my head around it. Before I go ordering supplies to run some tests, I thought it would be worthwhile to gain some insight from you guys. Anyways, as you probably know, total internal...

Hi folks, So everyone at some point studying QM deals with reflections from 1D finite potential wells using the TISE, but something that I never covered was how to talk about or calculate the forces involved in turning around that particle. I tried to work something out below, but I'm not...

Homework Statement The situation below is based upon the image of an object in the presence of a sheet with a small hole and an object that reflects an image onto a screen when shined with a light. The problem is below: Write an equation that shows the relationship between the length of...

Homework Statement A plastic plate with refraction index of 1.5 is placed in the interior of a micro-wave oven which operates with a frequency of 2.5 x 10^9 Hz. If the micro-waves are perpendicular to the surface of the plate, what is the minimum thickness of the plate so that the maximum...

Hello, I was just reading optics and I thought that if photon doesn't has mass it can't be accelerated.. If it is so then how it gets reflected off a smooth surface, why don't it just passes from the plane. As any reaction force by the plane couldn't accelerate it , it mustn't rebond as...

Hi, I'm interested in reflection of both particles and light off surfaces. My problem is associated with a model that I'm working on and can be divided into two parts as far as I see it. The first problem is the reflection of particles off the surface and the change in velocity due to...

Homework Statement Hi all. I am having trouble to understand the combination of transformation on a function: h(x)= a*f(b(x-c))+dHomework Equations The problem I am struggling with is the order of transformation; I do see that: f(x-c) is translation in the right since every event happen before...

I know emissivity parameter of Stefan-Boltzmann equation is related to both "absorption" and "emission" of the material. But is it related to "reflection" property of an object? If not what is the parameter that makes an object shiny?

this is a silly question but, how exactly does the reflection of a wave work? explain to me the mechanics/physics please. say you have a rope attached to a wall at one end. and at the other end there is a wave generator. a wave is generated and right when the wave front hits the wall, what...

Homework Statement Consider a random walker in one dimension, which can take right or left steps with equal probability. Assume that the walker starts at the location k>0 and there is an absorbing wall at point labelled as 0, that means if the walker reaches 0 the process stops and he stays...

Homework Statement A multi-mode fiber optic cable has a core diameter d = 115 mm, ncore = 1.42, and ncladding = 1.17. What is the largest possible angle θin relative to the surface normal that light can enter the fiber (i.e. pass from air into the fiber core) and experience total internal...

Homework Statement A light ray parallel to the x-axis strikes the outer reflecting surface of a sphere at a point (2,2,0). Its center is at the point (0,0,-1). The unit vector along the direction of reflected ray is ##x\hat{i}+y\hat{j}+z\hat{k}##. Find the value of ##yz/x^2##. Homework...

From this video of a Feynman lecture: At 39:30 he (Feynman) draws a line from the eye to the mirror, and then continues the line through the mirror, to represent where the image appears to come from (it appears to come from behind the mirror). Here he is showing the classical way of...

This is not a homework, this is concerning reflection and transmission of electromagnetic wave ( plane wave) at a flat planar boundary between two media. But the work in question is pure vector calculus. I ultimately want to proof if ##\vec E_I=\hat y E_I## then ## \vec E_R## and ##\vec E_T##...

A light beam of frequency f hits a mirror of length L at a distance 3/4 L from one end, which is fixed but can rotate freely around the axis as shown. The mirror has mass m and can be considered a rectangular plate. The light beam hits (and fully reflects) the mirror at a rate of N photons per...

Attached is a scanned of the page in question. This is regarding to Perpendicularly polarized plane wave. in equation (9.47a) at the lower left corner it is the distance ##x_i## to the origin. x_i=x\sin\theta_i+z\cos\theta_i\;\hbox {(9.47a)} That is not a distance. distance of ##|\vec...

I am reading Griffiths p387. It is my understanding that \tilde E(\vec r,t)=\hat r E_0 e^{j(\omega t-kr)} Where ##\vec r =\hat x x+\hat y y+ \hat z z## is the positional vector from the origin to the observation point ( x,y,z). \Rightarrow\;\tilde E(\vec r,t)=\hat r E_0...

Suppose TEM wave in +z normal to a boundary on xy plane at z=0. We know E & H are tangential to the boundary. Let ##\vec E_i=\hat x E##, be the incident wave towards the boundary therefore incident H is ##\vec H_i =\hat z\times \hat x \frac {E_i}{η}=\hat y H##. I have a few questions...

Any Conceptual Underpinning for Partial Reflection of Light (QED)? I recently partially read Feynman's QED. At one point, he says "The situation today is, we haven't got a good model to explain partial reflection by two surfaces;..." (page 24--can visit Amazon "Look Inside" to read) My...

When I view the sea surface for a few seconds (using a camera), some wave facets have very high radiance values. I understand that there is a distribution of slopes and that one can determine a statistical radiance distribution, but how do I calculated the reflected radiance from a single wave...

Homework Statement A beam of light is reflected off the surface of some unknown liquid, and the light is examined with a linear sheet polarizer. It is found that when the central axis of the polarizer (that is, perpendicular to the plane of the sheet) is tilted down from the vertical at an...

[FONT="Comic Sans MS"]Question [FONT="Comic Sans MS"]In many department stores, large plane mirrors have been placed high on walls or on projections from ceilings. These may be one-way mirrors that are designed to allow one-way surveillance of the store. From one side, this surface looks...

The equation for the change in momentum for total absorption of electromagnetic radiation is ΔU/c and that for total reflection is (2ΔU)/c. How could the momentum of electromagnetic radiation change if it is massless and travels at a constant speed c? Is the ΔU just a representation of a change...

Lets say we have a potential step with regions 1 with zero potential ##W_p\!=\!0## (this is a free particle) and region 2 with potential ##W_p##. Wave functions in this case are: \begin{align} \psi_1&=Ae^{i\mathcal L x} + B e^{-i\mathcal L x} & \mathcal L &\equiv \sqrt{\frac{2mW}{\hbar^2}}\\...

how does visible light carry with it? does this energy increases with increase in number of reflection?

What do the components of the following equation represent : http://www.mediafire.com/view/?0we6f9jkw26qi9o To be clear, this represents a wave of the form Acos(kx-wt) after being reflected off a wall. I understand that the ∅ represents the phase change of the wave after hitting the...

Hi! I need some help understanding something related to sound. I am currently studying a book called Sound Propagation. An Impedance Based Approach, by Yang-Hann Kim. There is a part where he talks about reflection and transmission of acoustic waves on a flat surface of discontinuity. He gets...

Homework Statement When the striking ray is held perpendicular to the prism, there are four general configurations possible (in the attachment below). Use the figure on the next page to determine analytically which of these four configurations will result in total internal reflection of the...

This is the question and the answer choices. I thought it would be mirror one creates E and mirror 2 creates F, but It's not... help?