Interaction Definition and 653 Threads

I've learned that you cannot deal with the interaction of a charge with its own field in classical electromagnetism. It is said, that this is simply the case with classical theory, and you have to deal with it. But how can this be? If accelerating charge is giving energy to the field, then it...

Homework Statement Electric charge is distributed along each side of a square. Two adjacent sides have positive charge +Q on each, two sides have -Q on each. What are the x and y components of the net electric field at the center of the square? (Each side has length "a").Homework Equations...

Hello! I need help with an exercise about the weak interaction: How do the mass, the q-value and the vertices depend on the half-lifetime of a decay? The myon decay has a half-lifetime of 0.0000015 seconds, the neutron decay has a half-lifetime of 607 seconds. Why is there such a big...

if you have 2 point dipoles p1 and p2 located at r1 and r2 respectively(all four are vectors) what's the energy of p2 in the field of p1? I know the general expression for the energy of a dipole in an external field Eo is U=-p * Eo but from there I get confused I can express the...

Okay i have a physics problem that i really don't get...pliz help me! A 6.0-kg block rests on top of a 7.0-kg, which rests on a horizontal table. a What is the force (magnitude and direction) exerted by the 7.0-kg block on the 6.0-kg block? i tried using the formula F sub a and b = F...

Considering the decay of certain exotic mesons, such as the following: B^{+} --> D^{0} \pi^{+} Apparently the decay proceeds via a weak interaction where multiple W boson exchanges occur. I was trying to nut out how this actually occurs, and draw up a sensible Feynman diagram...

Two small asteroids orbit each other in circular orbits. The distance between the centers of the two asteroids is 35 m. The mass of the larger asteroid is 3 x 10 6 kg and the mass of the smaller asteroid is 1.2 x 10 5 kg. a. )What is the magnitude of the gravitational force of interaction...

I am sick right now :frown: I just have cold symptoms, sneezing, runny nose, coughing, etc... I took some Sudafed 12 hour with the active ingredient, Pseudoephedrine. Since I took it my nose is running out of control, I am sneezing non stop, it's like someone opened up a faucet (not to be...

Is there such program available for download from the Internet; a program in which you can simulate interactions between elementary particles and atoms. So - it works like this: - you start the program, and there is just empty space (and literaly - it's vacuum (simulation equivalent (a ball...

Let us consider the http://en.wikipedia.org/wiki/Stern-Gerlach_experiment" experiment. The inhomogenuous magnetic field produces a drift force that can separate particles according to their spin and offer a possibility for a "measurement". This (very) small magnetic interaction can be...

Questions, questions, questions... I hope some one can answer these questions. thank you. :) 1. Describe the process of Compton Scattering, explaining carefully how both attenuation and absorption of X-rays occur. 2. How does the process of Compton scattering of X-rays depend on the nature...

Greetings! I've looked around in the FAQ and around the forums and couldn't find the answer to my question, so I've decided to ask. If however I did miss the answer, I apologize. Well, it's quite elementary actually. I am wondering if it is correct to assume that no two solid objects...

There are two electriferous paticles,moving in the same v&direction,then in our opinion,there will be an magnetic effect,but in particles' opinion,there will not be,how to explain it in relativity?:confused: Thanks!

Energy is not an invariant quantity between different frames of reference. For example a particle having a kinetic energy in one frame has a zero kinetic energy in another frame. But what about interaction energy? If I know the interaction energy between 2 particles in one frame, how can I...

In my nuclear physics textbook (from 1988), there's a section which lists properties of the nuclear force, including one section about how the nucleon-nucleon interaction may depend on the momentum or velocity of the nucleons. (It talks mostly about the spin-orbit term, which is V(r)*(r x p) dot...

Hello, Does anyone know why in pionic hydrogen the strong interaction should be attractive whilst in kaonic hydrogen it is repulsive. I have heard it is something to do with a sub-threshold resonance but nothing more. Thanks Sham

I think I understand how signals can be sent by field disturbances, and that the disturbance is propogated at the speed of light. Now, I was wondering about the case where a stationary field is already set up and you place a test charge in that field. Does that charge move instantaneously...

Hi, I'm stuck on the following problem. Can someone please help me out? Q. A bead (particle) of mass m travels along a path described by \mathop r\limits^ \to = a\cos \left( {\omega t} \right)\mathop I\limits^ \to + a\sin \left( {\omega t} \right)\mathop J\limits^ \to + bt\mathop...

Spin Orbit Interaction Hamiltonian is defined as follows: H_{SO}=\frac{1}{2m_{e}c^2}\frac{1}{r} \left(\frac{\partial V}{\partial r}\right)L\cdot S How does one derive the above Spin Orbit Interaction Hamiltonian from relativistic treatment? Is there a good textbook that elaborates on...

I understand the difference between the two main Neutron decays but, is there an observable difference when an electron collides with a neutron compared to a positron colliding with a neutron? In particular, I need to know if there is a difference in the behaviour of the neutron.

Hi, I need some materials or instructions on how to simulate fluid-structure interaction ansys or modeling to finish my research in the next 6 months. Do you know where I can find some source to simmulate the fluid-structure interaction ansys, or places where I can download source? I...

Could anyone please tell me how to calculate quadrupole quadrupole interaction between two molecules having dipole moment zero? As quadrupole is a tensor quantity I get a 3*3 matrix for a molecule.

I've got to find the energy between two dipoles separated by a vector displacement r. I found what the energy/field of one such dipole is (see attachment), but I don't know how to combine the energy of two dipoles (P1 and P2) using those equations.. any help on a starting point? :confused:

The electromagnetic interaction can be described by the exchanche of virtual photons. These photons have a well defined momentum and can therefore be everywhere in space. So gets the em-interaction of two electrons smaller the more they are apart if these photons have no favourite position in...

Hi All, Im' trying for some members of my site toshow atomic interaction force (coulomb...) with some animations. Here is my first trial two ions with same but opposite charges... Is there an acceleration since attraction augments (like I did)? You need Flash player...

I want to gather some links about this. If you know of some good articles and can add some links to the stash, please do. The gravitational field is the geometry of spacetime and can be roughly equated with spacetime itself, or a general idea of the vacuum----the ideas tend to overlap because...

I want to be in a position where I can design hardware, then write low level codes on chips (firmware) to make the hardware adaptable to software. Let's take a dvd player for example, I am thinking that if I have to write firmware so that the hardware and software can interact, I think that I...

After reading quite many popular science about QM, I still didn't get a real understanding of the difference between a so-called measurement and just an interaction (if there's actually any difference). My understanding is that a measurement is an interaction "observed" in a way which allows...

From what i have read, electron energy is not the only thing split into energy levels - also vibrational, rotational and translational energy is quantized. But which part of the atom absorbs the electromagnetic waves which cause these energy levels to increase? Is it still the electrons as with...

There is an analogy of the phenomenon of curvature of space by mass. It is a sheet of rubber with the some mass placed on it. Then the deepening on a sheet is formed and all surrounding objects with only smaller (?) mass should sliding down to the mass lying on a deepening bottom...

Fermi Contact Interaction of Electrons with Nuclei About this interaction, is it the spins of nuclei which interact with the spins of electrons? So, if I draw the magnetic field line from the left nucleus via the pair of e- to the right nucleus and there is not anti-parallel field against...

Upon my recent studies i have discovered various methods of defining mass in various situations. It has come to my attention that mass is somewhat undefined without the use of interacting parameters. Your thoughts?

Excuse me, I'm learning about the genetic interaction and I think I can get pretty much explanation in the Internet but Google didn't seem to be really helpful now. So please suggest me some sites on genetics and I'll try out! Thanks alot!

Could anyone please provide (or start off) the proof of (2.4) of the following document? http://www-its.chem.uva.nl/research/complex_fluids/Teaching/LectureNotes%202004%20vdWaals%202.pdf Many thanks

Hello I have a query (Classical Electrodynamics) regarding Self Energy and Interaction Energy. I understand that the integral definition U_{tot} = \frac{1}{2}\int_{all space}k\epsilon_{0}E^2d\tau = \frac{1}{2}\int Vdq represents the total electrostatic potential energy of a system and...

Does observation really mean interaction?? For example if something didnt interact with something else(for example proton A is far away for anything else) it would be in a superposition but would collapse into a normal state(decoherence) when it interacts(say proton A bumps into electron B)...

In the Residual Strong Interaction, energy and momentum are exchanged not through gluons but through exchange of quarks, for example in the soft hadronic scattering of a pi + and proton. Is the interaction mediated by a single meson or by two quarks, and if the latter doesn't this violate quark...

Can somebody give me good reference and links for gene interaction.I am in dire need of it. Regards drdolittle

I have a problem in understanding the dependence by isospin of strong interaction. In this potential one have a lot of operatorial terms which include central, spin-spin, tensor force, spin-orbit terms, and all this four terms multiply by a factor isospin-dependent (tau_i dot tau_j). I don't...

Hi, i have a particle physics exam in 2 days and am confused on pion decay via the weak interaction, namely: pi[-] ->muon + anti-muno neutrino Thankyou Ray Veldkamp

We know "asymptotic freedom" says that the interaction between particles, such as quarks, becomes arbitrarily weak at ever shorter distances and stronger with range The quarks are connected like being on a rubber band: (string) I have the following questions: 1) While the quarks get...

without the interaction we can't measure the field so interaction should come first which is against the literature.

I've heard that the weak interaction actually governs fusion between hydrogen especially in the sun, how does this actually works?

I wonder how the radiation will interact with matter on a hypothetical place where the atoms have no electrons. Will the photons and particles will interact with matter to produce any effects like that on earth. I don't think there will be any compton effect, photoelctric effect, pair...

Is there a version/subfield of QT that models the interactions between different wavefunctions? Something like Newtonian mechanics, but on the wavefunction level. E.g. you have two wave functions of (x,y,z,t), and you use the functions to find when and how they would affect each other and what...

I wonder if there are any gases that react to applied E/M field changes by changing their volume? Apart thermal stuff of course. I assume that piezo electrics apply to solids, but how about gases?

Hi! I have a beautiful picture of some interaction that I want to explain with the standard model. I think it's probably a famous one, but I have no idea where & when I found it. If anybody recognises this data, then I'd be very happy to hear what it is... For now, I am guessing something...

[SOLVED] Lights interaction with matter When light (photons/waves/whatever) comes into contact with matter, what are all the possible outcomes? Anyone mind listing them out with an explanation for each?

I'm posting this here because psi phenomena are typically not accepted as scientifically valid, and also because there have been a number of "if I saw valid, repeatable scientific evidence for psi I would believe in it" types of posts in this forum. Here is your valid, repeatable scientific...

i know that other planets in our solar system have lightning storms and as far as i know its natures way of keeping the electric field between ground and atmosphere in balance, but what would happen if this system had a "glitch" and an imbalance occured, could the atmosphere discharge into...