Negatively charged particle with spin 1/2. A component of mundane terrestrial matter, and part of all neutral atoms and molecules. It has a mass about 1/1800 that of a proton. Its antiparticle is the positron.

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Do electrons get accelerated or decelerated by the atoms of the anode during X-rays production?

The electrons striking the anode get deflected by the heavy nucleus. Though the speed may or may not change, the direction of motion changes which leads to acceleration. The charged particles emit ...
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94 views

Visualisation of electron

first things first, I'm not by any means a physicist nor a student of physics. I study graphic design. Theme of my bachelor thesis is visualisation of physical and mathematical phenomenons, long story ...
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37 views

Does positron-electron annihilation preserve enough info to reverse exactly

An electron-positron annihilation can produce a pair of gamma rays. In the reverse process, known as pair production, can the gamma rays carry enough information to determine the resulting ...
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108 views

Uncertainty Principle and single-slit diffraction [closed]

A beam of 50eV electrons travel in the x direction towards a slit of width 6 micro metres which is parallel to the y direction. The diffraction pattern is observed on a screen 2 metres away. Use ...
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2answers
56 views

Speed of electrons in resistors

What affects the speed of electrons in a resistor? If two resistors are connected in series, they both have the same current; same number of electrons passing at a point per second. Suppose one ...
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94 views

What is the Poynting vector of an electron?

On chapter 27 of "The Feynman Lectures on Physics Volume II: Mainly Electromagnetism and Matter", Richard Feynman says: Finally, in order to really convince you that this theory is obviously nuts, ...
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72 views

why do metals feel cold when electron moves at Fermi velocity?

This might be a very elementary question. Considering that electrons in typical metals have very high Fermi velocity, why is it that when you touch a metal you feel cold? My intuition tells me that ...
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20 views

Photon absorption by a hydrogen atom : [duplicate]

How does the photon absorption takes place in a hydrogen? The classical mechanics shows the absorption of photonic energy resulting in the excitation of atom. Intuitively, a photon with frequency ...
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1answer
28 views

Can all energetic photon excite an electron?

Consider a hydrogen atom, to excite the electron to a higher orbit, it should interact with photons of energy equal to that of the energy difference between the two states. If the energy of photon is ...
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39 views

Will Positron Cause flow of electricity?

Recently someone told me about antimatter. Antimatter is something that is completely opposite to matter. What I would like to know is let's say this universe was made of Anti-Matter. So since the ...
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1answer
24 views

What happens when an electron and an EMR meets?

The electron on an atom gets excited to a higher level when some how the energy is transferred to the electron. But I can't understand it. I'm no expert of physics. What happens when the electron in ...
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88 views

Are the left-chiral and right-chiral yukawa couplings equal?

I guess another way to ask this is: Does the "physical electron" spend EQUAL time being a left-chiral and right-chiral fermion, on average? Clarification: The electron switches between (-1/2 T3, -1Y) ...
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1answer
65 views

Does the gravity affect voltage in a circuit?

The electric current is a flow of electrons, which have mass (small, but it is still a mass). So, considering a planar circuit, do the properties of the electric current (voltage, intensity) change ...
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17 views

Help Understanding Correlations In Many Particle (Beam) Physics

I am having a lot of trouble looking at the statistical properties and having some sort of intuitive sense of correlations among different properties of many body systems (in particular charged ion ...
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31 views

Infinite Larmor precession

Say an isolated electron (meaning it's not part of an atom) is at rest and we turn on a homogeneous magnetic field around it. The electrons' spin undergoes the Larmor precession (except in the case ...
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What is Rehm-Weller equation should look like?

Rehm-Weller equation which defines the energy change for photoinduced electron transfer according to Lakowicz "Principles of Fluorescence Spectroscopy" should look like: $\Delta ...
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20 views

Couting the occupied states in band structure

I work with several dft codes and I have produced the band structures of some doped semiconductors with their plots. The problem I have is that I do not know how I can analyze the band structure and ...
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1answer
81 views

Why are permanent magnets permanent?

Let me see if I get it right. When an iron bar is attracted by a permanent magnet it becomes a magnet itself because all of its magnetic domains start to point in the same direction. When the iron bar ...
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1answer
59 views

Can we calculate L-S coupling without Dirac equation?

It is known that there exists an orbital and spin angular momentum coupling for an electron moving in the atom. And the Hamiltonian can be directly derived using Dirac equation. I want to use a ...
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29 views

Why free electron has orbital magnetic moment?

I was about to ask why don't we use electron beam instead of atoms in Stern-Gerlach experiment, then I saw this question and my question become why free electron has orbital magnetic moment...
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183 views

How is a photon measured?

If photons transmit the electromagnetic force, which is observable: the photon or the electron? Do we ever directly measure a photon, or do we only measure it's effect on electrons. For example ...
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Self-energy of electron from classical reasoning

If it takes energy to group charge together(self energy) how can it be possible for every single electrons, etc, to have exactly same amount of charge? (think of if we hold some sand in our hand, then ...
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28 views

Question on calculating the number density of free electrons in the sun's photosphere

I am writing a paper on the effect H$^-$ (a hydrogen atom with an additional electron) has on the opacity in the sun's photosphere. As such, I need to calculate its abundance. Doing so is ...
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1answer
27 views

How can nuclear decay both annihilate and create?

This'll be back to basics for many of you, but here's something I still don't get. How can nuclear decay of an unstable atom both create and annihilate positron-electron pairs? You have an unstable ...
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58 views

Charged particle singularity

Is it possible to manipulate magnetic/electric fields, similar to magnetic confinement technologies/penning traps, to compress charged particles into black holes?
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61 views

The “classical radius” of the electron [closed]

According to one theory, the mass m of the electron arises simply as a consequence of the electrostatic energy of its electric field, through Einstein's famous expression ε=mc^2, where ε is the field ...
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108 views

If protons and electrons had similar masses

If electrons and protons had the same mass, would they still be in a stable orbit around their barycenter, or would they eventually collide? Similarly, a positronium(or protonium) only lasts extremely ...
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49 views

Is it possible for electrons to carry more than one charge?

Sorry if this has been asked before. Could also be a really basic question (new to electrical study). I am a bit confused about the relationship between electrons and charges. So what I understand is ...
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34 views

Charge density within radius r from the nucleus

The probability of finding an electron within radius $r_b$ for Hydrogen near the center ($r_b<< a_0$) is approximately equal to zero (according to 1s orbital curve). Does this imply that the ...
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Why don't free electrons fall from metals if shaken?

This is a question we were asked at a physics lecture.
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4answers
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Can neutrons be synthesized purely from protons and electrons?

Can neutrons be synthesized purely from protons and electrons? Note: I'm looking for reactions that do not require neutrinos or any particles besides just protons and/or electrons as reactants.
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1answer
31 views

Why in PN junctions the octet rule is dominating electrostatic repulsion?

The depletion region in PN junctions is created by charges from the N part diffusing into the P part, thus completing an octet of covalent bonds in the P part. This shift however leaves positive ions ...
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71 views

Photoelectric effect Experiment - What's the voltage bias of the set up?

What's the bias of the setup? Forward / Reverse? I'm doing a photoelectric effect experiment.The experimental setup involves a photocell, which has an emitter (cathode) Potassium and a ...
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1answer
21 views

Foucault currents with a simple pendulum

I have this diagram : It's a kind of pendulum; when it swings, it passes through a small aera where there is a magnetic field. Therefore, the electrons moves towards the bottom because of a Lorentz ...
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1answer
48 views

Question about one of the problems of the Bohr model

This is probably extremely basic physics that I don't know, but I'm still going to ask: Say in hydrogen, according to the Bohr model the electron is "really" orbiting the proton, and as a consequence ...
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1answer
141 views

Can an electron stand in place of proton like a ghost standing in place of you?

The atomic orbital refers to the physical region where the electron can be calculated to be present, as defined by the particular mathematical form of the orbital 1. The picture below shows the $1s$ ...
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Does electron being many places at the same time violate Physics laws?

The following passage has been extracted from the book Parallel Worlds, by Michio Kaku: Because of uncertainty, the electron does not exist at any single point, but exists in all possible ...
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76 views

What makes electrons lose energy?

As far as I know from physics lessons I got at school, electrons go up to higher energy levels when they capture a photon. But, once an electron is at a given level, what makes it go down to a lower ...
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172 views

What is the difference between photoelectric effect and Compton scattering?

What is the difference between photoelectric effect and Compton scattering? These two effects explains interaction of photon with electron. Why in photoelectric effect whole energy of photon is used ...
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1answer
45 views

Kinetic energy of an electron in synchrotron

The question states as follows: An electron is accelerated in a LINAC (LINear Accelerator) so that it's kinetic energy is 1.00 GeV. Then it is transferred to a synchrotron where it's energy (didn't ...
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2answers
95 views

What does volume means at the quantum level?

The volume of the electron is the space bounds in which it is contained says the @CuriousOne. But how can we define the volume in such a small range. If we immerse a cuboid into a vessel full of ...
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Does an electron occupy a definite volume? [duplicate]

The proton is about 1.6–1.7 fm in diameter. Quoted from Wikipedia. That is,The proton just occupies a definite volume or a definite space. But I can't find the radius of an electron in ...
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32 views

In low voltage (3-12V) DC applications, which is safer to be exposed or touchable + or - terminal?

The - side has a surplus of $e^{-}$s and the opposite is true for the + side of the power supply. Does it not matter, or depends on your configuration / contact with Earth? Please explain!
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58 views

Drift velocity of electrons with changing area

What would happen with the drift velocity of a cylindrical resistor's diameter increases, with a given voltage between its terminals? According to the expression: \begin{align} ...
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2answers
85 views

If stars are ionized, where are the electrons?

As far as I know, universe is electrically neutral so, If stars are ionized, where are the electrons?
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73 views

What is the speed of an electric spark/arc in vacuum?

I am just curious about the nature of an electric spark, how fast are the electrons moving? Will these electrons slow down when the spark occurs through a dielectric? (e.g., air)
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37 views

Are the electric charges of an electron and a proton equal or approximately equal? [duplicate]

I read in Auletta's quantum mechanics (section 11.2) that the charge of the proton is, apart from the sign, approximately equal to that of the electron.. What ...
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What causes the random movement of particles inside a conductor?

I'm reading about currents in electricity right now, and it was mentioned that even if there's no electric field inside a conductor, charged particles inside are still undergoing random movement. I ...
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28 views

Doppler effect for the electrons emitted from ions moving at a particular velocity

If I have ions moving in X axis (along both directions; positive X axis and negative X axis) and if I irradiate laser along the positive X axis, electron will be ejected from the ions (if I am using a ...
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1answer
31 views

Reconciling electron subshell configurations and the Pauli exlcusion principle

I'd like to prefix this with an apology: I have no formal training in QP, and most of what I know has been obtained by reading Wikipedia. As such, it'd be really helpful if any answers took my lack of ...