Maxwell Definition and 507 Threads

Guys, Let me ask you the silliest question of the year. I am looking at the Maxwell equations in their standard form. No 4-dim potential A, no Faraday tensor F, no mentioning of special relativity - just the standard form from a college-level textbook. I know that the eqns are NOT...

Hello, i was given 100 x,y random numbers, and was asked to find: Using vmin = 0, 5 *vmax as bounds on the x-axis, and P(0) = 0, P(vmax) as bounds on the y-axis, generate a set of velocities vi where i = 1,...,n producing a set of random numbers from a distribution function. (When such a...

Hello, I have a quick question that is made up of a few parts. 1) How can you show the maxwell speed distribution via an experiment? Looking at the diagrams I've made in my notes, the properties of the curve are rather common sense, but there is something else i'd like to know about the...

Hi guys, I am reading griffiths electrodynamics. I have a question. How does Maxwell equation suggest that the speed of light is same for all observer? I know Maxwell's equation gives a value of C. How can we infer that it is same for all observer. Special relativity just assumes that the...

Should it be added to the Cauchy stress to calculate a "total stress", or it doesn't have such a physical interpretation as a surface force(EM field force is usually considered more of a "body force")? Certainly when the MST was first derived before aether theories were made superfluous by...

Homework Statement Find vrms from the Maxwell speed distribution. Basically what I need to solve is the integral a\int_0^∞ \! v^4e^{xv^2} \, \mathrm{d}v Where ##a## and ##x## are constants. Homework Equations $$a\int_0^∞ \! v^4e^{xv^2} \, \mathrm{d}v $$ Where ##a## and ##x## are...

I have a couple questions pertaining to electromagnetic waves and Maxwell's equations. I will list them numerically, for clarity: 1. From the textbook, "once [wave] is created it is self-sustaining and independent of the source." Is this statement only true when it exists within a vacuum? I...

hi everybody. i just wonder. can we add new material library in ansys maxwell 3d(v.16) manually. especially magnets?

The question is in the image file. I am stuck, I don't know how to start. Can someone guide me please?

I am designing an energy harvester consisting of a magnetic spring. The figure is given in the attachment. I have done the magnetostatic analysis (using Ansoft Maxwell 2D). But, now I am facing problem with - Force vs displacement curve of the moving magnet To calculate the output power...

hi. I am new at maxwell. i have work on some examples but i want to learn how can i do a linear motor project. i didnt find any examples ( pdfs ). where can i find some pdfs?

Hi guys, I would like to know if the answer given to this thread is correct https://www.physicsforums.com/showthread.php?t=457405 I got the same doubt, is the expression for the tensor given in cartesian coordinates or is it general to any orthogonal coordinate system? Thanks in advance

hi. I am new at maxwell 2D and 3D. i found some pdfs and examples. I am working on the rotational actuator example which in that pdf 1. and i got an error: Fatal internal error (2:14:49 Eyl 09, 2013) Simulation completed with execution error on server: Local Machine. (2:14:49 Eyl 09, 2013)...

I'm having a little difficulty understanding the use of derivatives in Maxwell's equations. Eg. \oint E . dl = - \frac{d\varphi_{B}}{dt} this says that a changing magnetic flux in time, produces a potential difference (and electric field) in space? I noticed that its a full derivative, and its...

Hi All, If anyone could help me with a problem I'm having, it would be great. I've been using Ansys Maxwell for about 6 months now, and I've gotten the hang of it. I mainly simulate 2 phase inductors. Until yesterday, I've had no problem, but for some reason, I'm not getting any...

I have an easy question but nonetheless I have not been able to find the answer: within the context of special relativity, in particular with light clocks, where the two opposite mirrors of a hypothetical light clock are traveling along very fast, they nonetheless do not leave the emitted...

I made a spreadsheet to plot the 3d speed distribution from the MB probability function. It matches the peak and fall-off of published graphs. I then tried to integrate it by summing over interval widths times probability. I thought the area should be 1. My result is around 5 or 6. I've tried...

[This is mostly about notation] I was working on a problem where I had to prove that div(B) remains invariant under lorentz transformations. That was not too hard, so I came up with div(B) = \partial_{\mu} B^{\mu} must equal div(B) = \partial'_{\mu} B'^{\mu} so I did a...

Hi, I am using a Human body model which I built for some simulation studies. I was trying to pass DC current through the Human body and though my Project completed the simulation successfully I got the below warning message. Can anyone please help me interpret it? The error log is as...

Dear I have problem with determine the minimum speed in this problem , I think the the maximum speed equal to the average speed and the most probable speed can be obtain by derive equation and equally to zero .Is my solution correct? The speed distribution function for N particles in a...

why was maxwell given the credit to gauss's integral (flux) equation?

"Dr Ian Chapman has been named one of the UK’s top young physicists by the Institute of Physics, winning the 2013 Maxwell Medal, given to those who excel early in their career. The scientist from Abingdon has joined the likes of Stephen Hawking in being awarded a national prize for his...

Homework Statement Show that a static, spherically symmetric Maxwell tensor has a vanishing magnetic field. Homework Equations Consider a static, spherically-symmetric metric g_{ab}. There are four Killing vector fields: a timelike \xi^{a} satisfying \xi_{[a}\nabla_{b}\xi_{c]} = 0 and...

When can be used (\frac{\partial S}{\partial V})=\frac{P}{T}?

Hello people, I am interested in tutorials about coil design for Maxwell 3D. If anyone have good material or knows where to find it, let me know. Regards,

Homework Statement In the Maxwell eqn divD = ρ (sub f) What does ρ sub f represent? Homework Equations The Attempt at a Solution Does is represent volume density of charge?

Homework Statement You will recall from our discussion of the Franck-Hertz experiment that the energy difference between the first excited state of mercury and the ground state is 4.86 eV. If a sample of mercury vaporized in a flame contains 1.02×10^20 atoms in thermal equilibrium at 1613 K...

Homework Statement You will recall from our discussion of the Franck-Hertz experiment that the energy difference between the first excited state of mercury and the ground state is 4.86 eV. If a sample of mercury vaporized in a flame contains 1.06×1020 atoms in thermal equilibrium at 1563 K...

Hi experts, I wonder anyone of you have an idea on whether we can include a discrete component (specifically a capacitor) into an "Ansoft Maxwell 3D" eddy current design. Little more description: I do have a specific eddy current design with a coils. I need to add a series capacitor and...

Homework Statement 1)How do we obtain the formula of torsional rigidity ,c=∏nr^4/(2L) ?From experiment? then how do the ∏ come from? How do they know the n here is the rigidity modulus? Why it is not the young's modulus? 2)Is Maxwell needle method same as the torsional pendulum? Both can be...

[b]1. Homework Statement [ How do I get I1( the moment of inertia of the picture b) ?is just a math problem but really no idea. Homework Equations I=mr^2 The Attempt at a Solution maybe centre of mass . Guide will do . please help , thank

I'm having some trouble calculating the stress tensor in the case of a static electric field without a magnetic field. Following the derivation on Wikipedia, 1. Start with Lorentz force: \mathbf{F} = q(\mathbf{E} + \mathbf{v}\times\mathbf{B}) 2. Get force density \mathbf{f} =...

I'm starting my study in eletromagnetism and I would like to know how do you deduce the eletric field produced by a single particle of charge q placed in the origin. The magnetic field is constant so by Maxwell equations, the rotacional is 0 and the divergence is constant. Is this enough to...

I am designing a 2D model of a three-phase core-type transformer in ANSOFT MAXWELL 14.0. While doing so I have encountered a strange problem. Start of the problem:- While designing the transformer, I wanted to incorporate core losses. So, I did the following steps:- Excitations -> Set...

According the the kinetic theory of gases, molecules moving along the x direction are given by Σx= (1/2) mv^2, where m = mass and vx is the velocity in the x direction The distribution of particles over velocities is given by the Boltzmann law p(x)=e^[(-mv^2)/ekT] where velocities range from...

Hello, I am a student from Germany and I stared my first project using ANSOFT Maxwell. I have read several tutorials and have a few questions how to simulate my problem. Hope I can find some help here. First my problem: I have two identical magnetic disks. These disks are so positioned...

Hi PFers. I am interested in Maxwell Boltzmann Distribution. I have searched in Internet for the derivation but I am not satified with them. Can somebody show me the way to derivate it? Thanks. ψ(v)=(m/2*pi*kT)^(3/2) e^(-mv^2/2kT)

Is it enough to see the covariance of the wave equation the fourth-vector potential (\phi, \bar{A}) satisfy? I mean, is this enough to prove the covariance of Maxwell equations? The equation would be ∂_{\mu}∂^{\mu}A^{\nu} =\frac{4\pi}{c} J^{\nu}

Hello! I am having an issue with getting any graphs on inductance or induced voltage. In the attached circuit: What I have is a 28Vac source w/ 400hz and 2 coils (R=18.6ohm each) that are connected with a common. In the model: I have a core in the center that will be able to move up...

As per Maxwell reciprocal theorem, it is valid only for elastic materials and structures indergoing small displacements.That is k12 = k21, kij = kji hence stiffness matrix is symmetric. Howbver, I just have been going through MY OWN written programs for geometric non linear problems and I...

Homework Statement The field E(r,t) can be written as a Fourier expansion of plane waves E(r,t)=∫E(k,w)e^{i(kr-wt)}d^{3}kdw with similar expansions for other fields. Need to show the derivation of kXE(k,w)=wB(k,w) from Faraday's law ∇XE(r,t)=-∂B(r,t)/∂t and also the derivation of...

To preface my problem, you should know what I'm deriving. When I try to find the most probable speed of a classical, nonrelativistic particle as described by the Maxwell speed distribution I find that it is vmp=(2*k*T/m)^(1/2). The kinetic energy associated with this particle would then be...

I want to know if the Maxwell speed distribution is the following. An ideal gas system of n particles, say constrained to the unit box, has the phase space ([0,1]^3 x R^3)^n. That is, [0,1]^3 for the position of a particle, R^3 for the velocity, and all to the n since there are n particles...

Hello, Where can I find a good explanation (book) of the derivation via Noether's theorem of the three momentum and angular momentum operators of the usual maxwell lagrangian ? Thank you!

I was reading a book, 'Introducing Quantum Theory' by J.P.McEvoy, and I find it difficult to understand in details of Maxwell Distribution, Thermal Equilibrium, Fluctuation, Wein's law and Planck's quantum theory, so I am finding it difficult to follow Einstein's explanation of photoelectric...

Hi. I am trying to understand Maxwell's equations. I am used to Gaussian units. The following sums up what I do not understand. (Or at least one thing I do not understand ... ) Let x0 be a position situated in a vacuum, with no photons in it, next to an infinite pane of glass. Ions arrive at...

Hey all, This has been bugging me for quite a while now. My question is essentially about how one shows that Maxwell equations are invariant under Lorentz transforms. Writing them in index notation, it is usually appealed to that all terms involved are Lorentz tensors (or contractions thereof)...

Homework Statement The three quantities Vmost probable, Vaverage, and Vrms, are not the same for the Maxwell speed distribution in 3D. If you restrict the gas to only be one dimensional, are these three quantities equal to each other? Justify your answer with a short explanation. Homework...

Hi everybody, I would like to compare inductance (self and mutual) calculations using FEMM and Maxwell 13, both 2D problems. In FEMM this is very simple and I just use an axissimetric solution, enter the desired frequency, currents and get the results. When using Maxwell...

I have for a while been trying to understand the setup of this equation in calculating the collision flux of a gas through a given rectangular surface of area A: Number of collisions in a time interval Δt is (\frac{N}{V})AΔt\int^{∞}_{0}v_{x}f(v_{x})dv_{x} where f(v_{x}) is the fraction of...