Reflection — 400 discussions

Hi all, I have two questions about light in Special Relativity. (I'm going to pad these questions out with a few statements about my understanding of length contraction and time dilation, so you can see how I currently think about it and clear up any misconceptions if I've got the basic idea...

I'll get into the details why I need this for below but first I'll explain what I'm looking for. I basically need a flat sheet of aluminum or any plastic in grey or black color that doesn't provide specular reflections, yet is smooth enough to not have any noticeable texture when looking with...

I have seen many articles lately regarding planned manned missions to the moon and Mars but the question of radiation protection constantly comes up. Engineers keep proposing various shelter designs that use local materials (regolith) as a concrete base to absorb harmful radiation so that the...

Homework Statement Discuss the main advantage and disadvantage brought about by a reflection coefficient being very small, and hence highlight the attributes that an ultrasound scanner must have to fully exploit very small boundary reflection. Homework EquationsThe Attempt at a Solution I am...

I am working on HFSS and designing Antennas for LOW RCS , in all previous works they calculate the S11 parameter for the unit cell then make an array form this unit cell and calculate the RCS , my question is what is the relation between S11 and RCS and why we calculate S11 for the unit...

Hello, I have a question or perhaps a few questions regarding light and mirrors. When we point light at a mirror, it gets reflected back. But we can see the point light (assuming that it is a laser for the sake of simplicity) at a surface opposite to the reflective surface of the mirror. What...

In a previous thread, we discussed specular reflection from a stationary and moving mirror, and argued that the momentum transfer was always normal to the mirrors surface. I became curious as if this was true in the case of diffuse reflection. But I'm not sure how to calculate that. It's...

In Total Internal Reflection, the beam can still lose some energy as it reflects off the boundary of the medium it is within. This isn't covered under the Fresnel equations. The energy loss is probably lost in the form of evanescent waves. I tried searching for the formulae describing the...

We know that reflected light undergo a phase shift of π in EXTERNAL REFLECTION but there is no phase shift in INTERNAL REFLECTION . Does this violate Stokes Relation, which states that every reflected beam undergo of phase shift of π ?

What is the difference between the photon interaction mechanisms in emission due to absorption and reflection?

In refraction of spherical surfaces, We derived the formula to be: ## u_2 L^{'} = u_1 L + (u_2 - u_1) R## Where ##L^{'}## is the reciprocal of the distance of the image. ##L## is the reciprocal of the distance of the object. ##u_2## is the refractive index of the medium that the light ray is...

Light is Reflected from the surface of the object or pass through it(interior) and then the light is reflected ? Sorry for my "noob" question i am a 3D designer just looking for some more knowledge Thanks in advance

https://eng.libretexts.org/Core/Materials_Science/Optical_Properties/Metallic_Reflection According to this article,metals are good reflectors at low frequencies.What about at high frequencies like visible or UV spectrum?Will this show deviation

Homework Statement 2. Homework Equations 3. The Attempt at a Solution [/B] I tried to solve this question with the general formula n=sin i / sin r. 1.5 = sin 30/sin r, r = 19.4 = 19 which is option A. But option A is incorrect. Please guide me where am I wrong..

I was testing a small spherical mirror with sunlight and wondered about something. The size of the mirror is 2.5cm. The spot size of the reflected light grows over larger distances but it doesn't seem linear. For example, at a meter or less, the spot is very close to the mirror size but at a few...

Homework Statement When a workman strikes a steel pipeline with a hammer, he generates both longitudinal and transverse waves. The two types of reflected waves return 2.4 s apart. How far away is the reflection point? (For steel, vL = 6.2 km/s, vT = 3.2 km/s). Homework Equations Unknown...

The reflection of the line 5x - 7y - 13 = 0 by the line y = -x is ... A. 7x + 5y - 13 = 0 B. 7x + 5y + 13 = 0 C. 7x - 5y - 13 = 0 D. 7x - 5y + 13 = 0 E. 7y + 5x + 13 = 0 This one I totally have no idea. Like, at all.

Hi All, Due to the differences in their conductivities, but considering that both the metallic and the glass plane surfaces produce mirror images of objects, is there any difference in the explanation of the mechanism of reflection of light in these materials?

How a reflection grating works as diffraction source?

Hi, I have a question in definition of reflection/transmission coefficients in TE/TM modes. Let's see TE polarization case. The reflection coefficient for the magnetic field is defined as: However the transmission coefficient for the magnetic field is defined as: Now, let's see the TM mode...

If light encounters -normal- matter, the electromagnetic aspects of the influence of the electrons will be interacted with (I'm ignoring any stress contributuins to gravity) which is (scattering matrix?) either nothing at all (translucency) due to quantisation, or absorption. Is this correct...

Hi, if I read the article (see link) I get confused: Is it emission or reflection? If it is emission, how is it possible that the photons are emitted to one side? (Unfortenately I do not have access to the original article.)...

Hello, For calculating the mean power at a specific cross section of a waveguide, one can calculate the mean value of the temporal function of Poynting Vector, P(t), where P(t) is the ExHy-EyHx. Note that I am not talking about phasors or a sinusoidal state. If I integrate over the waveguide...

I know that only light with polarization in the plane of the "stripe" gets reflected. What i need to know is if a single metal stripe could reflect such polarised light at ONLY the angle equal to the angle of incidence or do only a whole array of stripes produce specular reflections? Sources...

If I had metal stripe significantly longer than the wavelength but less wide than one wavelength and it would be at an angle in the plane perpendicular the length of the stripe to to the incoming wave, would itireflect specurarly or diffusely?

Homework Statement Hi good morning to all. The problem at hand states, that the points A (3,0) and B (5,0) are reflected in the mirror line y=x. Determine the images A' and B' of these points. I've done that using the reflection in the line y=x which i know to be \begin{bmatrix} 0 &1 \\ 1 & 0...

Hello there, I have a problem with this image from the Michelson Morley experiment in which one tries to calculate the time taken by the light beam to traverse the arm of interferometer perpendicular to the velocity of the frame in 'ether'. So the problem is, Are laws of reflection being...

In his popularized version of QED (Strange Theory...) Feynman explains reflection from an air-water boundary (including total internal reflection) by summing up the amplitudes of various paths that bend at the boundary but are straight everywhere else. As we add more contributions, we see a...

Homework Statement Note : There are no minus signs in first two options . Homework EquationsThe Attempt at a Solution The wave is propagating in +z direction whereas the electric field is varying in x direction . On reflection , there is a phase change of π . Also wave starts traveling in...

Let's consider a simlified ionosphere. It is a cold plasma without magnetic field and without electron-neutral collisions. The refractive index for radio waves is nf=sqrt(1-(w/wp)^2) (w is the frequency of the radiwave, wp the plasma frequency). It easy to demonstrate that the group refraction...

Homework Statement A transparent film( n = 1.45) is placed on a glass surface( n = 1.14) and is illuminated by light ( incidence angle α = 60°. What is the minimum thickness d1 of film such that reflection of light with λ is minimized, while if the thickness is d2 then with the same λ the...

The mirror that I'm talking of, is situated in Hazarduari Palace in Murshidabad, West Bengal, India. This place was once the capital of Bengal under the Nawab before the British defeated the Nawab in the historic battle of Plassey, 1757. The history is not that important here, but the mirror...

What is exactly happening when the light hit a surface of a mirror? I know it is not same as a bounce of ball from the wall, because of constant speed of light for example. So I suppose the light is absorbed by electron of reflecting material. This probably define the materials who are...

So, I was just working out on color and reflection but then turned a little bit confused. The main phenomenon we study everywhere is that a colored object absorbs light of all wavelengths excepting the light of its own color. Then comes the problem. As per that, if I beam a GREEN LASER on a RED...

So I'm having a introductory study on waves and there's something that i can't understand when dealing with reflections on a fixed end. We have the general solution for the wave equation: ## y(x,t)=f(x-vt)+g(x+vt)## Supposing that the fixed point is in the origin we have the boundary condition...

Homework Statement I am working on a lab report, and I am a bit stumped at these questions: How does reflection affect the intensity of the microwave? Is all the energy of the wave striking the Reflector reflected? Does the intensity of the reflected signal vary with the angle of incidence...

I have a problem with the phase of an electric field as it is reflected by and transmitted through a dielectric interface. At the boundary between the two media, all waves must exist simultaneously and the tangential component must be equal on both sides of the interface, right? Therefore for...

So here's a mystery one of you may be able to solve. I noticed that the reflection of light from the fingerprints on my iPhone screen depend on it's orientation toward a light source. For instance, use your finger to make two perpendicular smudges across the screen. You'll find that the smudge...

Homework Statement How to demonstrate that we see colour of an object due to reflection of light? Homework EquationsThe Attempt at a Solution We see an object because photons from that object come to our eyes. The photons from the object comes to us due to radiation or reflection. If the...

how total internal reflection of light takes place in terms of quantum world?

How would polarized light behave after being reflected by a diffuse surface, such as a white wall? Would it still be completely polarized or would it be more randomly polarized? Would whatever effect takes place vary significantly with different diffuse materials? What about a mirror? Surely...

Hello, I would like to calculate the difference between a white surface wall surface and the same kind of wall but with brown outer surface. I would like to know the reflection and absorption indices and then calculate the surface temperature of the wall in the two solutions at the same...

I am discussing physics with a friend and we need someone to confirm a thing that we're not agreeing on. We are discussing incident light that is passing through different geometries, and I want to know how the light behaves when it reflects inside a half sphere (of glass for example). Maybe...

Homework Statement The transmitter is on the left, and the receiver is on the right. The transmitter transmits radiowaves. The distance between them is d = 50.0 m & each one's height is h = 35.0 m. The receiver can receive the radiowaves directly from the transmitter, or through reflection...

Do receivers only receive signals or they emit emf?

Hi all, Is there any way to impart a transformation upon a radio wave's reflection from an object, such that the reflected wave is different from the original signal in some way (frequency, phase, etc.)? Not sure what this would require (maybe a constant and active coordinated interference...

Hey! :o I am looking the following: For each point $Z$ let $\delta_Z$ be a reflection around the point $Z$. For which points $Z$ is $\sigma_g\circ\delta_Z$ a refection along a line, where $\sigma_g$ is the reflection along the line $2x+3y+4=0$? I have done the following: A reflection...

Imagine I have a 10x10x10cm cube filled with a scintillating material (material capable of generating light when energized). Three cameras are looking at this cube from three orthogonal directions (x, y, and z). Light is generated inside the cube and is refracted as it leaves the cube and...

Hey! :o Let $g$ be a line with equation $g:ax+by+c=0$ in Hesse normal form. I want to show that the reflection across $g$ is described by \begin{equation*}\binom{x}{y}\mapsto \binom{x}{y}-2(ax+by+c)\binom{a}{b}\end{equation*} At the reflection across $g$ it holds the following for the image...

During a rainy day the clouds appear black but not so normally (in good climatic conditions) I think its something to do with light so I posted this query . If its not, sorry.