Coupling Definition and 355 Threads

Okay, I get that we need it to block DC while allowing the AC to pass. But if we have to block DC, why apply it in the first place? Is it because we apply it to a certain level and then we want to keep it to that level so we block any further interference by DC? Thanks.

Hi, these days I have been trying to understand the essentials of the so-called topological insulators (TBI), such as Bi2Te3, which seem very hot in current research. As i understand, these materials should possesses at the same time gapped bulk bands but gapless surface bands, and spin-orbit...

Hoping that one of you electrical wizards may be able to help me out! I have a 30A DC HP power supply and a 1000W stereo amp that I want to use create a 10mT static DC magnetic field superimposed on top of a 1 mT AC magnetic field. To generate the AC field I have a 1 uF snubber cap. in series...

What is the relation between the coupling coefficient and the fraction of flux from one inductor going through the other inductor?

So I understand that the tensor product of two vector spaces constitutes a new vector space. In the case of spin coupling you have some arbitrary vector |x,z> where x represents the spin state of particle 1 and z represents the spin state of particle 2; bot spin states being general 2 element...

What is the difference between coupling and constrain equations in ansys

Hi everyone, I am trying to figure out what is the coupling of a surface plasmon with a photon for the generation of a surface plasmon polariton. In fact I don't understand what a coupling is in this context. Some texts say that for the coupling to happen is necessary that the dispersion...

Dear all, would anybody know of references regarding experimental constraints on the running of the weak coupling ? This running is rather slow, and I guess we do not have evidence one way or the other, but since the SM and the MSSM have opposite slopes, I'd like to see what kind of...

Hi. In Hund's second rule, it seems that we calculate the value of L simply by summing the L_z components of the individual electrons. But L has to do with the eigenvalue of the L^2 operator, i.e. the eigenvalue is L(L+1). So how can this be correct?

I just read something about the creation of deuteron in the first step of the pp cycle. Given that you have the reaction: p + p -> d + e^+ + v_e, where e^+ is a positron and v_e is an electron neutrino. Since there is a neutrino present, it is a weak interaction. In addition, as the interaction...

What is the minimal coupling principle? Is it some sort of a prescription? Thx

Hi, I was reading a lecture of qft and I found that two equations: \begin{flalign*} i \gamma^\mu \partial_\mu\psi_R - m\psi_L=0 \\ i \gamma^\mu \partial_\mu\psi_L - m\psi_R=0 \end{flalign*} after splitting in two Dirac's equation with Weyl's projectors. I found that really interesting that the...

I hope someone can help me out here. I am having difficulty understanding what the difference is between the spin orbit interaction and LS coupling scheme in atoms. I know the spin orbit interaction (or spin orbit coupling) is due to the interaction of say an electron's spin with it's orbital...

I realize that energy is a touchy subject in GR in dynamical situations, and people argued for a long time whether or not gravitational waves carried energy. But it sounds like there has been agreement for quite awhile now that they do carry energy. Since in weak gravity situations, we can...

More specifically, I have an NMOS oscillator, where the output is taken from the source terminal. I have to couple the output (50 Ohm load) with a coupling capacitor, but is this going to affect my calculations of the resonant frequency of the circuit? In my case, I have a Clapp oscillator...

Let's say I'm considering the 3p^2 electrons. From the Pauli Exclusion Principle, we know that two electrons cannot have the same state, which in this case means ml and ms cannot both be the same for each electron. What this means is that the following 6 terms must not be allowed: m_{l1}...

Homework Statement Hi all, I have this project i have to write but i am having trouble getting the necessary materials to aid my writing. The project topic is the influence of crossing angle on amplitude in cable to cable coupling. It is a magnetic coupling problem and i am supposed to design...

Homework Statement The 4p → 4s transition in 19K produces a pair of lines at 766.49nm and 769.90nm. Estimate the value of <(1/r)dV/dr> for the optically active electron in 19 K Homework Equations The Attempt at a Solution help needed urgently please. All i know so far is...

First let me preface this by saying by physics-fu is remedial at best. I am a neuroscientist by training, but need a little help with piece of equipment I am designing, so any ideas or input would be greatly appreciated. Basically, I need to figure out a way to efficiently couple a light...

Homework Statement One of the n=5 states of hydrogen is split by spin-orbit coupling into two levels with an energy difference of 0.0039 cm^-1 . Determine the 'l' quantum number for this state and predict the analogous splitting for doubly ionised Li . Homework Equations The fine...

Hi, In particle physics, what does 'coupling' mean? I can't find a definition anywhere and books just assume you know what it is. For example, "the Higgs couples to light particles". Also, what does it mean to say that something strongly or weakly couples to something else? Any help...

Hello All, I've been playing worth some DDS output filter and amplifier circuits in the simulator and have run into an interesting little problem. I want to make an output that can range from 0.2Hz to 20Mhz and so far I have built a very nice reconstruction filter that can give me a very...

You still have not answered the question; What are the two forces of the weak angle coupling constant? We have spin and charge as known forces. If you can not specifically identify spin or charge as one of the two forces involved in the weak coupling constant than for all you know there...

Homework Statement I have to find the Fermi Coupling Constant using my measurement of the muon lifetime. My measurement is 2.1786x10^-6s Homework Equations G_F=\sqrt{\frac{192.pi^{3}}{\tau.m_{\mu}}} The Attempt at a Solution I tried plugging in the numbers that I have and I get...

Homework Statement Just a quick question, the Z can couple to leptons and there antiLeptons and quarks and there corresponding antiquark. Is the coupling constant just Gz for all these interactions? Or is it Gz.Sin(z) for some and not for others? Iv seen different notation and am wondering...

The Schrodinger equation with the minimal coupling to the Electromagnetic field, in the Coulomb gauge \nabla \cdot A , has a continuity equation \partial_t \rho = \nabla \cdot j where j \propto Re[p^* D p] (D is the covariant gradient D= \nabla + iA . My question is: is there any...

Hi - I live full time in an RV that is surrounded by aluminum - essentially a faraday cage, except for a few rather small windows. I'd like to mount a WiFi antenna on the roof and run a cable in a window or thru a small hole. Basic issue - how to get a good signal from a campground WiFi...

Suppose there is a field that couples to the stress-energy tensor. For simplicity, assume it's a scalar field coupling to T=T^\mu_\mu. Since contracting Einstein's equations with the metric yield the relation R = 8\pi G T, is it correct to say that the field also couples to R?

I am not really solving an exercise for homework so hopefully this general forum is OK for my question. For my thesis, what is attitude control of a flying object with a reaction wheel, I am learning the basics from this NASA Technical Report: http://www.hot.ee/ronn/design_glob_anal_...

Ok, so we're running a compressor rig powered by an air turbine that keeps breaking. I've been asked to review the rotordynamics for the entire system. Prior to my employment, the compressor shaft itself was evaluated, however they want the effect of the turbine and the spline couplings to be...

When it is said that the relative strength of weak interaction is \ 10^{-5},what does this mean? On calculation I am getting \alpha_w=\10^{-3} with \ G_F=\ 1.16\times\ 10^{-5} \ GeV^{-2} I had an impression that \alpha_w should be \ 10^{-5}.Which one is correct?

I can't find the value of the Yukawa coupling g, for neutron-proton scattering for example, where the Yukawa potential reads - g^2 exp(-m*r) / r. Can some1 tell me at least an approximate value?

I was trying to explain the origin of spin-orbit coupling to a beginning student and I used the following naive analogy: An electron orbiting around the nucleus "sees" the nucleus rotating about itself (the electron) in its own (electron's) reference frame, thus this is like a current loop...

how does the exchange coupling mechanism work that produce the ferromagnetic properties of materials?

background: I have a HNMR spectra and I am trying to figure out what is coupled to what. There is a set of 4 doublets where it is know that there 2 sets of coupled doublets. the doublets have j-values of 8.8 @ 8.04ppm, 8.8@ 7.58ppm, 8.4@7.39ppm and 8.4@7.00ppm. While I may have assumed that...

All right, my 1st-year college chemistry class is just beginning NMR, and I really have no clue what's going on. But what caught my eye was how the relative intensities in hydrogen coupling is roughly predicted by Pascal's triangle. Is this because of probability? For a quartet, the number...

I need to obtain a toroid for inductive coupling to medium voltage power lines. The frequencies to be coupled are between 10 kHz and 900 kHz. Bear in mind that at power frequency (50 Hz), the current will be high (up to 100 Amps). Anyone have any idea on a magnetic material that can achieve...

What is Universal weak coupling hypothesis?

hi i just read this article,which discussed about getting the Schroedinger's equation for a particle in a em field by transforming the psi, http://www.vttoth.com/gauge.htm .can anyone please tell me if we can get the dirac's equation for a particle in a em field by transforming the psi thanks...

Hi I am struggling to answer this question: The input coupling circuit of the amplifier shown in the figure consist of an RC network, with R = 1 kW and C = 5mF fed by a sinusoidal voltage source of r.m.s. amplitude of 200 mV. Assuming that the input impedance of the amplifier is, at all...

I learn that increase of the beam size of the laser before coupling it to the fiber can increase the coupling efficiency of it. Can I know why is this so? Maybe the fiber is of very small diameter, and the focal lens in front of the fiber can't focus all the laser to this small diameter...

Homework Statement A truck that has a mass of 5kg is being pulled up a slope by a string. The truck is also pulling another truck of mass 2kg up the slope with a rigid coupling inbetween the trucks. Ths slope is inclined at 10 degrees to the horizontal. The 5kg truck has a resistance of 8N and...

i am now reading the book by woodgate: elementary atomic strucure, 2nd edition. on page 62, he discusses the spin-orbit coupling in hydrogen atom, and calculates the first order shift of the energy due to this effect. I have some doubt about his procedure from eq.4.25 to eq.4.27 the...

hello our prof talked about oldham coupler and showed us some animations of how it works, but didn't mention about where and in which machines it is is used, anybody knows some practical uses of oldham coupler and some examples of machines this coupler is used in? thanks

Hi, I am doing an experiment to investigate the propagation loss in some nanophotonics structures. The laser light is coupled to the input of the DUT chip via a tapered lensed fiber and the output of the chip is go through a objective then a photodetector. The chip is design for...

URGENT- gravitational coupling constant value? I urgently need to find a value for the gravitational coupling constant since the only on ei have is from wikipedia. I've looked on the partcicle data group but couldn't find it there. Anyone? Thanks Karnten07

Hi guys, Where can i find the most up to date (accurate) values of the standard model coupling strengths at the mass of the Z boson? Thanks Karnten07

Hi guys, Where can i find the most up to date (accurate) values of the standard model coupling strengths at the mass of the Z boson? Thanks Karnten07

I heard in the school a long time ago, that photons do not have a coupling with an electric field. Can someone explain it detailed? Does someone have good online literature? Thanks in advance!

Homework Statement There is a coupling attached two two shafts. The shafts have opposing and equal torques on them with a radius, r. Assuming the shear stress in the bolts used in the coupling is uniform, figure out how many bolts would be needed to make the max sheer stress in the shaft equal...