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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How does one determine whether an object will make an EM wave refract in a qualitative way?

for example, i have a vague notion that the actual answer is that the permittivity and permisivity are different in each different material, so all waves refract at every boundary, but we only call it ...
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What is the difference between phase difference and path difference?

I have learnt that path difference is the difference between the distance travelled by two waves meeting at a point. If that is path difference,then how will one know what is phase difference and how ...
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67 views

Why doesn't the magnetic field polarize when polarizing light?

If the magnetic field doesn't polarize does it follow the electric field path of propagation? or does it vanish?
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312 views

What is the fringe separation in Young's double slit experiment?

In the double slit experiment, a pattern of dark and bright bands appears on the screen. Is the fringe separation the distance between two bright bands? Question: In a double slit experiment ...
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1answer
164 views

Relationship between slit size and wavelength in diffraction

Almost in every book on physics we can find a statement like "diffraction gets stronger when the size of the slit is comparable to the wavelength". Let's say we have a wall in a bathtub with a slit in ...
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1answer
37 views

Is polarization of a wave just a description of its motion in three dimensions?

Since a polarization of the wave is described by complex numbers, we can try to give that mathematical formalism geometrical meaning. With having two different axes, one imaginary and other real, it ...
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1answer
63 views

How to “derive” the wave equation without refering to strings?

The wave equation in $3$ dimensions is simply: $$\nabla^2\psi = \dfrac{1}{v^2} \dfrac{\partial^2}{\partial t^2}\psi,$$ and the intuition behind this is that at each point of space with coordinates ...
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27 views

Properties of 3D waves

I have a few questions about 3D waves: Are all 3D waves types of electromagnetic radiation? Are all 2D waves mechanical?
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61 views

How to calculate loss due to Gaussian beam divergence of a laser going through multiple lenses?

To better explain my question, I will need to give a brief description of the configuration used in 2D MEMS switches. So, the next figure shows a configuration of a 2D MEMS switch, a light beam ...
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1answer
54 views

How could electromagnetic waves propagate through space although they have no electrons?

How could electric fields in these waves propagate through space although in space there's no electrons for the electric field to be formed? is there another type of charged particles that carry the ...
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1answer
38 views

Power of Shockwaves

My question is about shockwaves and their power when they are created/how do they lose their power? Let's say that we have ground 0 with 10 grams of TATP on it. The detonation velocity of TATP is ...
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1answer
78 views

Period of Double Slit Experiment

What is the period of the pattern from the double slit experiment? It varies along the pattern right? Namely I'm confused because when considering two point sources (See: Period of Interference ...
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22 views

Tuned Mass Damper

I was learning about the different applications of resonance and one of them is the tuned mass damper used in buildings. One thing I am confused about is as to why the mass attached to the building ...
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1answer
49 views

Help in understanding the derivation for Fresnel Distance?

An Aperture of size $a$ illuminated by a parallel beam sends diffracted beam (the central maxima) in angular width approximately $λ/a$. Travelling a distance $z$, it aquires the width $zλ/a$ due to ...
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75 views

SIngle slit diffraction and location of dark spots

In single slit diffraction, why (according to the equation for $\theta$) do successive dark spots exist at whole number intervals ($n=1,2,3, \ldots$) and not half? The correct path difference for ...
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1answer
96 views

Does sound cancel itself out?

If there are two 10 x 2 x 1 foot rectangles in space and they are lined up so if they hit each other there will be no spots that are not hit in the front of the rectangle. Then they are pushed forward ...
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1answer
238 views

Deriving the group velocity of a wave produced by some basic cosine waves with unequal amplitudes

Consider some basic cosine waves of the form ${E_i} = {E_0}\cos ({\omega _i}t - {k_i}z)$ with different amplitudes, frequencies and phases. We know a combination of such waves could result in a wave ...
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90 views

Dispersion-less media

As far as I know, vacuum is the only dispersion free medium for electromagnetic waves. This makes me wonder if there are any other dispersion free media for these waves? (Experimentally established or ...
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41 views

Rijke tube: Why Sound is maximum when heated 1/4th length from bottom of tube

Why is it that the maximum sound coming from a Rijke tube happens only when heated wire gauze is placed at 1/4th the length of the tube from the bottom. According to Rayleigh: If heat be ...
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43 views

What's the local law of propagation of disturbances

In Vladimir I. Arnold's Lectures on Partial Differential Equations, Chapter 3 Huygens' Principle in the Theory of Wave Propagation, which is devoted to the proof of Huygens principle (original one by ...
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29 views

How to represent a multiple in the frequency domain

So, in my previous question Where does this formula for prediction of a multiple wave come from?, I get that using this picture: we have so far written the time it takes for a multiple to travel ...
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60 views

Boundary conditions for 2D helical waveguide

I'm interested in looking at standing wave solutions for the wave equation on a 2D annulus, with the twist that the annulus is "streched" in to a helix in 3D, but so that the rings themselves are ...
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31 views

Light Apparent Brightness

Let's say I have a triangular light source. From that light source I want to calculate a pyramidal frustum (tetrahedron with no apex). How would I calculate the maximum bottom area where light would ...
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171 views

Simulating the Interference Pattern of Fraunhofer Diffraction by a Single Slit

I'm attempting to simulate the Fraunhofer diffraction pattern due to a single slit. We know that the intensity at an angle θ is $I(\theta)=I_0Sinc^2(\beta)$ where $\beta=kb{Sin(\theta)\over 2}$ ...
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Question regarding waves squeezed

in one MOOC I am taking, the professor had a slide stating "when squeezed into a narrow space wave is amplified". I am not sure I understand what he meant by that, and I am trying to think into terms ...
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128 views

Waves produced by a mass of water on the calm sea surface

Suppose we have a parallelepiped shaped box full of water on the surface of the sea. Suddenly the box disappears. What is the shape of the waves vs. time caused by the fall of the water contained in ...
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64 views

antiferromagnetic spin wave

I have a hamiltonian that is derived from a spin wave energy dispersion calculation for a nearest neighbor interacting cubic antiferromagnet. After a Holstein-Primakoff transformation and making a ...
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75 views

3D interference visualisation software

We are searching for a software program that simply helps us to visualize in 3D the interference of planar waves of multiple sources (frequencies) and as sepctrum on a wall. Something like a well ...
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101 views

What's the physical interpretation of constants in Laplace equation and diffusion equation?

What's the physical interpretation of constants in wave equation and diffusion equation? $$u_{tt}=c^2u_{xx},$$ $$u_{t}=ku_{xx}.$$ Please introduce some reference about mathematical modeling of ...
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38 views

Bass and Treble-Car Steroes

In a car which phenomenon, diffraction or the resonant frequency of the car, lends itself more to the ability of bass to go farther? Related Answer: Why do bass tones travel through walls?
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50 views

the effects of an ln-prime transformation to physical models

I have rather a "toy" type of modelling-problem that appeared to me along a book I am writing on number theory. I would be outmost thankful for any concrete or inspirational answers, including ...
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103 views

Historical aspect of wave theory of light

Huygens thought light as a wave. Wave is a propagation of physical disturbance. We now know that light is electromagnetic field. Electric and magnetic field fluctuates here. What Huygens really ...
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66 views

Counting the modes of the vector potential in a coulomb gauge

With a view to quantising the EM field, consider a classical free field in the absence of charge and currents, we can take a coulomb gauge, $\phi=0, \partial_kA_k=0$. The physical fields in terms of ...
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66 views

Minimum thickness of bubble ensuring max reflectance

A soap bubble has index of refraction of 1.33. What minimum thickness of this bubble will ensure max reflectance of normally incident 530 nm light? Ans is 99.6, but how do I get that? I am ...
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91 views

The interference of waves and factors that affect cancellation?

If you had two repeated disturbances on the surface of a water, I know interference will occur. However, if I move the two sources of disturbances closer together, why would the 'gaps' between each ...
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196 views

Sum of intensity of reflected and transmitted waves

The given state: Let $\psi$ be a wave that passes from medium $a$ to medium $b$. Let $A$ be the amplitude of $\psi$. Let $R$ be the amplitude ratio of the reflected wave $\psi_r$ and the original one, ...
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307 views

Intensity of the diffraction pattern of the double slit

I am trying another approach for my last unanswered question. (Bounty still on for 3 days. Anyone? Please?) Note that this is not the same question but a greatly simplified version concerning a much ...
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0answers
79 views

Can a wave propagate in an elastic fluid in the absence of volume forces?

A motion (wave) $\mathbf{x}: \mathcal{B}_0 \times [t_0,t_1] \to \mathcal{E}:$ such that $q-o = \mathbf{x}(p,t)=(p-o)+\mathbf{a}_0 cos(\mathbf{k}_0\cdot(p-o) - \omega_0 t)$ can propagate in an elastic ...
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159 views

What is the electric field part of an EM wave? Radiation field or the induction field?

Look at this image: I wonder if the electric field is from the induction field from a vibrating electron or the radiation field? If it is from the radiation field, as I suppose, than can someone ...
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General wave equation derived from Maxwell's equation

I need to derive the general wave equation from Maxwell's equation without using the divergence therom (because I haven't read multivariable calc yet!). My physics book gives one but I don't fully ...