# Tag Info

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First of all we all should know the meaning of the phrase "the electron is accelerating." It does not mean that $a=\mathrm{d}v/\mathrm{d}t$. The accelerating electron means that the electron is changing its electric field. Obviously no electromagnetic radiations will be produced during orbital motion of the electron because the electron doesn't radiate ...

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In nuclear fussion electrons and protons can fuse to form neutrons with the release of photons.

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To provide a graphic version of Punk_Physicist's answer, we have the Feynman diagram for that particular interaction: This diagram evolves in time from bottom to top, ie take a piece of paper, and run it upwards along the diagram to see how the system evolves. We have an electron and a proton coming towards each other, then we see them interact by ...

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There are two kinds of "earth" being talked about here. There is: The kind that aims to use the ground itself as a "return path"; and A protective "earth", which is actually a separate conducting line laid throughout a building. For the "return path" earth of 1. there are several ways wherein this will work: There is actual conduction (i.e. drift of ...

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Actually according to my opinion it give you a shock but it is negligible. If you give a high energy and try to make contact with earth it will neutralize by giving a little to you. The reason is, if there is a good conductor like body it goes through the body other than only earth. Just take a lightning application and think of that.

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Part 1: Conceptual/physical intuition Since there is an electrostatic attraction between the 2 particles, then when they are apart they are at a higher potential energy then when they are together. Here's an analogy: Physically, this situation is like having a ball at the top of a hill overlooking a valley or well. The ball will roll down the hill and ...

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Check this link here. This is a quote from the website: When an electron falls from infinity towards a proton it acquires 13.6 electron Volts of energy to reach the ground state “orbital” around the proton. I have always wondered why it does not go all the way. Apparently, its Debroglie wavelength has to fit” around the “orbit radius” for it to occupy a ...

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In this article electrons seen in a bubble chamber are shown. The spiral is an electron knocked off from an atom of hydrogen , a bubble chamber is filled with supercoole liquid hydrogen in this case. Th accuracy of measuring the tracks is of order of microns. The momentum of the electon can be found if one knows the magnetic field and the curvature. The ...

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Earthing something means dumping the electron flow into the earth. Since the earth is so big, it can absorbe/give a practically infinite amount of charge without changing potential, this means that you can treat earth as a reservoir of ready to use electrons. If you plug the phase of your home power line into the ground (without safety devices in the ...

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Fermi pockets (or Fermi surfaces) are contours of Fermi energy in the Brillouin zone. Depending on the effective mass $m^*$ of quasi-particles, the Fermi pockets can be divided into electron pockets (if $m^*>0$) and hole pockets (if $m^*<0$). For weakly interacting Fermion systems, according to the Fermi liquid theory, all the low-energy physics ...

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i know the energy required to excite the electron would be enormous. I'm not sure but it could be around the plank mass. I'm not exactly sure how that factors into what forces are holding it together. As for what kind of field mass it generates inside the cloud i would think maybe its of order of a single photon of around the wavelength matching the size of ...

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If the electron is point-like, the Poynting energy expression is infinite and thus it is useless for calculation of the energy of the electron in the Einstein sense $E=mc^2$, which is finite. If the electron is cloud-like, the Poynting energy expression is finite and may give part of electron's energy; not all of it, since some non-electromagnetic forces ...

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How did Lyman discover his series in hydrogen atom? He was directed into spectroscopy by his advisor. At the time the equipment was pretty poor for spectral measurements and much of his time he spent trying to get good spectral wavelength measurements. Part of the measurement error ended up coining the term "Lyman ghosts" in the spectral lines due to ...

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The Coulomb logarithm is a heuristic cutoff. For length scales beyond the Debye radius, electrons in a plasma see a smoothed electric field, not the $1/r$ potential of the neighboring electrons. Hence, when computing two-body scattering, for electrons with an impact parameter too far out, that particular charge will be screened and cut off. Thus, in any ...

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One model is to say that the atom is in an impenetrable spherical box, and solve for the wavefunctions. See Y P Varshni Accurate wavefunctions for the confined hydrogen atom at high pressures J. Phys. B: At. Mol. Opt. Phys. 30 No 18 (28 September 1997) L589-L593. The Fermi Contact Term (electron density at the nucleus) greatly increases as the size of the ...

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Yes, it is possible. The simplest qualitative answer to this is that, at the microscopic level, the electrons in a conductor are dictated by quantum mechanics, which is inherently probabilistic. Velocities and positions are rarely ever totally excluded from a given value; it's just insanely unlikely for a single electron to attain that given value. ...

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As Ross pointed out, two scenarios are possible: free electron / electron as part of an atom. They're treated in two totally different ways. Free electron: free electrons can't really "absorb" photons. They can collide with them, and some things can happen (this, for instance). Those types of collisions are described by QED and there are a bunch of ...

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Note that electron in isolation can never absorb or emit a photon. It is only a system of 2 particles (*) than can. P.S. 2 or more; Theoretical consideration of electron in a static field requires something to create said field.

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When an electron absorbs a photon, it remains an electron and the photon disappears. The electron energy and momentum are altered to account for the energy and momentum the photon was carrying. For a free electron, it will not be possible to balance energy and momentum simultaneously. There will have to be another interaction to make that work. If the ...

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If the electrometer leaves are wetted by the liquid, capillary forces (wicking) will pull them together and not allow them to easily separate. DOI: 10.1021/la902779g DOI: 10.1109/84.232594 DOI: 10.1021/ja983882z http://web.mst.edu/~numbere/cp/chapter%203.htm 3.1.4 Application to Parallel Plates Take two clean microscope slides, immerse them in clean ...

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Quantum scientists came to the realization that they had to forget about the why question. Did you notice that the answers above only talk about what happens, but not about the mechanism by which it happens? There are some calculations that one can do about the energy of photons causing electrons to move off at a particular angle, and the energy of the ...

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To rephrase: an electron approaches an cation. Most likely result: a photon is emitted and the electron is captured. Added: The way I see it: an ion and an electron at a large distance apart. This would probably be an electron in a very high orbital of the ion. As the electron approaches, all the natural forces affect the electron and the electron slows ...

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The electrons and holes are quasiparticles which can be hardly represented by a free-particle model due to their exchange-correlation coupling. For instance, at the extremely low densities, when low-energy electron and hole arrive at very short distance to each other, they do not necessary recombine, they probably form exciton, a stable bound state of the ...

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This is an interesting question. Let us consider a current carrying wire and see what's going on inside it. Consider two streams of electrons as shown above. They move with a drift velocity $\vec{v_d}$. $These$ $streams$ $can$ $be$ $thought$ $of$ $two$ $current$ $carrying$ $wires$ $each$ $with$ $the$ $thickness$ $of$ $an$ $electron$. Each carries $equal$ ...

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The magnetic field is created by the electrons; thus it would not disrupt the movement of the electrons.

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Here, we shall discuss about relative permittivity $\epsilon_r$. Permittivity $\epsilon_s$ of a substance is the measure of the $resistance$ offered by a substance against the flow of electric field lines. Greater the value of $\epsilon_s$, fewer will be the number of electric field lines flowing through the substance. $\epsilon_r$ is defined as the ratio of ...

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Your value is within the range of literature values. Hydrocarbon Lithography on Graphene Membranes states "the Fermi wavelength of the electrons in graphene of 0.74 nm". Many references cite this value. Another reference says ~0.14nm.

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