Waves are disturbances that propagate throush space and time. Classically, they travelled through a medium, disturbing the particles but not changing their mean position. Electromagnetic waves/particle-waves need no medium; they are disturbances in their respective fields.

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What's the difference between exchange spin wave and magnetostatic spin wave?

So far I've heard of three kinds of spin waves Magnetostatic spin waves (MSW) Dipole-exchange spin waves (DESW) Exchange spin waves (ESW) What's the difference?
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Mechanical waves edge between material and vacuum

I have been thinking about the propagation of EM waves vs. mechanical waves and some of their odd cases. One such case that I haven't been able to puzzle out is what happens when a mechanical wave ...
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155 views

“Derivation” of the Heisenberg Uncertainty Principle

Ok, so I posted this in the mathematics StackExchange, but got no response. The question I outline below is my textbook's "derivation" of the Heisenberg Uncertainty Principle. The "derivation" my ...
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48 views

Quantum Excitations

In the context of quantum field theory, is the schrodinger or dirac equation actually describing some sort of an actual wave in some field like light in EM field ? So all particles are actually waves ...
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26 views

How is the imaginary part of angular frequency omega related to the imaginary part of the refractive index?

I'm trying to find the attenuation constant (leak rate) $\alpha$ from the imaginary part of the refractive index of a lossy material. I have the eigen frequency $\omega$ for my structure which has an ...
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41 views

Doppler effect and light

Approaching the speed of sound in an aircraft is relatively difficult, because the closer you get to Mach 1, the denser the pressure is around you (sound accumulates causing vibrations). Is there a ...
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80 views

Why doesn't amplitude affect the speed of sound?

I understand why amplitude doesn't affect the speed of the sound AFTER the 'leading compression'. The extra force provided on one stage of the cycle is countered on the other stage. But shouldn't the ...
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22 views

Normal modes of two wires fastened together

The problem is to find the normal frequencies of the system formed by two fastened wires of length L, and different mass per unit length. I already wrote the boundary conditions, but I need to know ...
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37 views

What is the longest distance over which echolocation is effective?

Some animals, most notably bats, use echolocation in order to navigate and detect the location and size of objects and prey. This usually takes place over short distances. What are the theoretical ...
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71 views

Constructive and destructive interference in De Broglie matter waves

I'm a little confused about matter waves and especially interference. $\lambda = h/p$ The denominator is momentum and is thus reliant on mass. If we assume that the property holds for particles ...
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344 views

Chladni Plate Mathematics

I am a high school student doing an IB Extended Essay investigation concerning the resonant frequencies of Chladni plates of differing materials and sizes. Would someone please explain the definition ...
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345 views

The physical meaning of electromagnetic wave

What, fundamentally, is an electromagnetic wave? As far as I know, all wave phenomena are derivations of an oscillating processes, e.g. particles vibrating in a medium. I can't imagine a wave process ...
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79 views

Classical wave equation from fermions

Every time there is a classical wave equation, the underlying system is bosonic. For example, em waves are made from photons, sound from phonons (technically quasi-particles), etc. What would be the ...
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52 views

Is there an equation that tells you more about the amplitude of an object which is in resonance?

I'm a high school senior and I have to write a paper about resonance and differential equations. I've been searching the Internet for a long time, but I haven't found an equation that is properly ...
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131 views

Fourier Transform of ribbon's beam Electric Field

I have a monochromatic ribbon beam with $E(x)e^{i(kz-\omega t)}$ being the electric field's amplitude. I want to show that the lowest order approximation in terms of plane waves is ...
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151 views

Physical difference between two different attenuation coefficient functions

The attenuation of a wave through a medium can be modeled by the Beer-Lambert Law using an attenuation coefficient. If $I$ is the intensity, and $I_r$ is a reference intensity, then what is the ...
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80 views

Can we compute the magnitude of the stress caused by sound waves on a wall?

As a follow up to this question, Could we really compute the magnitude of the stress caused by sound waves on a wall? If so, How do we do that?
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95 views

After quantization of electron vibrations, do we need electrons anyway?

The title question is not ment in a general context, but one in which goes to the plasmon theory. In that case, how is are the statistics (boson vs. fermions) of plasmons determined? And is there an ...
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34 views

Is there a second order differential wave equation that only allows a finite set of discrete eigenvalues?

I tried constructing a second order differential wave equation that only allows a finite set of discrete eigenvalues by using the power series expansion such as \begin{align} A_{j+2} = ...
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26 views

To find the center of charge in current waveform

I have a circuit for which output current waveform has both positive and negative points. Now I want to get a center of the charge for this waveform (means where my net charge is concentrated ?). Is ...
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42 views

How do I get around the fact that boundary conditions don't apply in the equation's region of validity?

A tight string lies along the positive x-axis when unperturbed. Its displacement from the x-axis is denoted by $y(x, t)$. It is attached to a boundary at $x = 0$. The condition at the boundary is ...
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36 views

Stationary wave on a string

The problem says: A string lies on the x-axis, and is fixed at $ x=-a $ and $ x=a $. At $ t=0 $ we impose a transversal velocity given by $ a^2-x^2 $. Assuming that the velocity of the wave is $ c ...
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51 views

Number of wave modes in a cavity

I'm trying to calculate the number of acoustic modes that can exist in a room in a certain range of frequencies. I thought of using the Rayleigh-Jeans formula for the electromagnetic standing wave ...
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48 views

Can anyone outline the theory of plane wave Born approximation for direct nuclear reactions in detail?

Can anyone outline the theory of plane wave Born approximation for direct nuclear reactions in detail? Also What are the modification introduced in the distorted wave Born approximation? I was ...
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23 views

Conduction and propagation

What is the difference between conduction of electric wave in conductor and propagation of electromagnetic wave in dielectric? Why propagation term is used for dielectric and conduction for ...
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27 views

Calculating Dynamics of a Thick Sheet of Material

So I'm working on a computational neuroscience problem, and I'm attempting to model skin dynamics for use in some perception models. The problem is as follows: Imagine you had a two dimensional sheet ...
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65 views

Rotate the phase of a wavelet

Let's take a zero-phase Ricker wavelet which is given by: $$ \psi(t)=\frac{2}{\sqrt{3\sigma}\pi^{1/4}}\left(1-\frac{t^2}{\sigma^2}\right)e^{-t^2/2\sigma^2} $$ in the time domain which is often used ...
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25 views

How much can a thin layer of hi-speed material within a low-speed volume block a wave due to total internal reflection?

Consider a block of isotropic material with compression wave velocity associated with it, $v_1$. Consider a thin flat layer of high compression wave velocity $v_2, v_2>v_1$ that is buried within ...
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29 views

electron spin separation

I am having doubt whether the electron's up spin moment and down spin moment can be isolated from one another. If it got separated, will each moment acts as magnetic monopole (stable or unstable). ...
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71 views

Gerstner Wave Formula to Vertex information $(x,y,z)$

I have created a program, that draws a plane mesh, and allows to me edit or animate all the separate vertices along it. The idea behind it, is for me to be able to create a gridMesh based wave ...
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182 views

cause of maximum kinetic energy and elastic potential energy at the same point of a transverse wave in a string

Suppose a string element oscillating transversely in SHM having both kinetic energy and elastic potential energy travels with velocity $u$. Let $y(m)$ be the amplitude. When it reaches $y(0)$, it has ...
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51 views

Is there a consensus on the definition of wavelength for a solitary wave?

Solitary waves are by definition a wave of single nature so the usual definition for periodic waves does not apply. R. Dalrymple provides a definition but I saw a lot of other websites and papers ...
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69 views

What could be the distribution of an explosion energy of a mining-grade and seismic exploration explosives?

Seismic exploration involves the excitation of seismic waves using the industrially made explosive charges. What could be the distribution of explosion energy of such a charges? My guess is that it ...
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45 views

What is the physical meaning of group velocity for elastic waves through crystals?

In a chapter about phonons they define group speeds for elastic waves in crystals as the derivative of the dispersion relation: $$v_g = \frac{d{\omega}}{d{k}} $$ I wonder though how they come to ...
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38 views

I've been reading that it's possible to create a “mostly magnetic” wave, and I have a few questions

Would it be possible with the "mostly magnetic wave" to have it behave in such a way that it would be undetectable by radio triangulation? I read about the monument at the CIA headquarters that was ...
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41 views

is it possible to load a transversal wave with a longitudinal wave

like in communication engineering for sending information what we do, we take a high frequency carrier and modulate it with the message signal so can we do the same thing like take a high ...
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132 views

Standing Waves in Flutes

How do the waves produced in flutes have a wave characteristic while maintaining a velocity that allows them to travel to out ear? If it were simply a standing wave I'd imagine that they would ...
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90 views

Longitudinal EMAG wave?

I'm reading about optical waveguide analysis, and often come across the terms "transverse electric mode" vs. "transverse magnetic mode". As I unerstand, it means that the electric/magnetic field has ...
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93 views

How do you super impose two or more signals to occupy a fix area of space with the resultant summed wave?

Is it possible to super-impose two or more signals all sent from different directions as a standing wave with the resulting summed wave occupying a fix area of space that is also a complex area? Do ...
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55 views

What phenomenon is responsible for the evolution pattern of waves created by waterfalls?

I have been fascinated lately by the pattern of the waves created by a waterfall in my town. Specifically, the pattern shows a gradual decrease in the density of the waves as they travel away from ...
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141 views

Behavior of wave at boundary

Firstly, how is "density" of wave formulated as? Secondly, when wave, travelling in less density medium, meets with the boundary that has higher density medium next to, reflected parts of the wave ...
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187 views

How to derive a multi-reflection echo from a given single-reflection “trace”

Consider a one-dimensional semi-bounded "ray" (or thin "cylinder") of stratum (or just any homogeneous substance) which has several "features" along it's length (say, thin films). Consider a wave that ...
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336 views

Depth of sea and point at which waves break

Following up on this answer, is the point at which waves break on the sea shore a guide to the depth of the sea at that point? Could it indicate eg hidden rocks? Explain the direction of waves on sea ...
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137 views

Reflected electromagnetic wave relation

If incident electromagnetic wave is given as: $$\begin{align*}E_i&=A_e \cos(\omega t + bz)\\ H_i&=A_h \cos(\omega t + bz)\end{align*}$$ What would be relation for REFLECTED wave? Does it ...
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67 views

Reorienting a sensor axes according to particle displacement directions

Consider a sensor which is located inside the solid substance. This sensor is capable of detecting the substance oscillations along each of the three axes (usually orthogonal, but generally, any ...
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Transmission Line above infinite plane connected by impedance line - Is my drawing correct?

Okay, I was doing a question on transmission lines. The setup is a wire placed at distance $d$ above an infinite conducting plane. The impedance of such a line is $Z_0$. Then there is an impedance ...
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47 views

Reflection & Transmission curves of waveguides

I have simulated a grating-coupled waveguide in Comsol Multiphysics, the waveguide consists of 2 dielectric layers and air as the cover of waveguide. I have excited the modes of this structure by a ...
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21 views

Direct optical observation of the Arago spot: what would one see?

The Arago/Poisson spot is an excellent example of a constructive interference of diffracted light. In the traditional experimental layout, you observe projected light on the screen. The theory in this ...
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30 views

Instantaneous displacement of a traveling sine wave with an undisturbed starting condition

The equation for the instantaneous displacement of a traveling wave at time $t$, and at any position $x$ along the wave is: $$y(x,t) = A_{max}\sin(kx +\omega t + \phi)$$ But this is only valid ...
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Drawing the wave function for a wave packet

I have the following infotmation: Amplitude-Function: $U(k) = Ae^{-a|k-k_0|}$ Wave Function: $u(x,t) = \frac{A}{\sqrt{2\pi}} \frac{2a}{(x-vt)^2+a^2}e^{ik_0(x-vt)}$ Uncertainty in x: $\Delta x = 1$ ...