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 electron shells exist within equipotential regions?

I had to read up on equipotential surfaces recently and I noticed the pattern of equipotential surfaces around a point charge. The idea came to me then that since no work is done in moving charges ...
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33 views

Repulsion of electric charges

If a take a vacuum tube and put electrons in it and put a negative ion strip or something like that outside the tube will the electrons inside the tube start moving due to the repulsion of charges of ...
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1answer
33 views

Electricity is the movement of electrons or ions?

Electricity is the movement of electrons from one atom to another or the movement of charged negative particles (ions)?
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2answers
83 views

How do you rotate spin of an electron?

I can't seem to connect these two stories. Can you please help? I have heard that you have to turn electron by 720 degrees in order to get the same spin state. Has this been seen experimentally? How ...
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1answer
49 views

Work functions of ceramics/insulators

Is anyone aware of or know of a good source or means of estimating the work function of a ceramic material? Typically, work functions are given for pure elemental metals, rather than for compounds, ...
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2answers
123 views

Are electron fields and photon fields part of the same field in QED?

I know in classical field theory we have the electromagnetic field. And Maxwell's equations show how electromagnetic radiation can propagate through empty space. I also have been reading about QED ...
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1answer
19 views

Why would a photon striking an electron “make both recoil”? [duplicate]

Why would a photon striking an electron "make both recoil" as I read in an answer to another question. If the photon is massless, how can it make an electron change momentum?
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5answers
255 views

Why do we need a wave function?

Assuming our only aim is to solve double slit experiment (or other problems that can be mapped into that). Knowing that electron does some strange thing not expected of a particle, we need a function ...
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2answers
48 views

Does the speed of electrons depend on energy?

I would like to know whether the speed of an electron depends on energy. If yes then in a circuit when electrons flow out of a resistor the energy decreases by a considerable amount, leading to the ...
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4answers
79 views

Can an excited atom have multiple electrons in excited states?

For an excited atom, is it possible for the atom to be excited twice, having multiple electrons in higher energy levels than for the atom in its ground state? If it is indeed possible, what is the ...
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1answer
25 views

What's the relation between molecular orbitals and electron density?

The way molecular orbitals are drawn represent the "encapsulated" space in which the wave function has a significant amplitude. How do I obtain from this the electron density? Is there a fundamental ...
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3answers
254 views

Are electrons miniature black holes? [duplicate]

For something to be a blackhole, it must have gravity and the radius must be smaller than the schwarzschild radius for its mass. -Electrons have gravity -Electron are theoretically believed to be ...
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0answers
70 views

Is an electron technically a set of two particles?

The electron - described as a four-spinor in the Dirac equation - transforms according to the $(1/2,0)\oplus(0,1/2)$ representation of the Lorentz group, so it is actually a direct sum of a left- and ...
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1answer
23 views

Is a CRT / Electron gun in need to be in a closed loop?

I'm trying to understand electricity and there for electrons. And so far i believe i am grasping it. But there are a few parts i have a hard time understanding. For example in as i understand it, in ...
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1answer
41 views

What is the factor that controls the speed of electrons accelerating in vacuum?Won't they accelerate infinitely? [duplicate]

We all know that speed of light can not be exceeded. So the question is if electric field accelerates electron in a vacuum tube with enormous length won't the electron accelerate till a point where it ...
3
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1answer
313 views

What proved Conventional sense wrong?

What fact proved for the first time that the conventional sense of current was wrong? And when it did happen? As a corollary of this question, why do we say that electrons have negative charge? Is it ...
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2answers
26 views

Units of rutherford singly differentiated cross section for secondary electron production

I have an equation that I have found in several papers which I am currently using for a project, including Waligorski (1986) and this book page 32. 4.2 BUTTS AND KATZ MODEL Butts and Katz ...
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1answer
26 views

where does the kinetic energy of electron revolving in nucleus go when photoelectric effect takes place?

we all have been studying that when photon is incident on alkali metal surface, photo currents are created due to ejection of electron after exceeding the work function.but the electron do have ...
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0answers
25 views

Are electrons matter waves? [duplicate]

While studying the de Broglie equations today I learned that electrons are particles that also act as matter waves. But in my text book I learned that there is a mathematical equation that says that ...
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0answers
16 views

Calculation of energy deposit of photon beam

Let's say I shoot a 1 MeV photon beam onto a volume. I want to know the ratio of deposited dose per path length for different materials (water and air) at a certain position (e.g. x=0) in the volume. ...
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1answer
31 views

Help me understand static electricity

This is what I understand about electricity: (The following information is paraphrased from the book CODE by Charles Petzold.) Atoms are made up of protons, electrons and neutrons. Protons and ...
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1answer
486 views

Does the spin of electrons imply a more complex structure than has been observed? [duplicate]

If electrons have no substructure and are considered point particles (according to the Standard Model), then how can they also have intrinsic spin? It would seem that the fact that they exhibit spin ...
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7answers
400 views

Momentum of stationary electron in a curl free vector potential

The essence of this question is simplicity itself: There is an electron in a curl-free $\vec{A}$ field. The electron is stationary so its m$\vec{v}$ momentum is 0. However, it has "momentum" from ...
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0answers
16 views

Gamma photon excitation of electron

Can a single high energy photon excite more than one electron in an atom?
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1answer
45 views

How do you calculate the free space wavelength of an electron? [closed]

The only thing I know about an electron is that its mass is $m_0 = 9.109 * 10^{-31} kg.$ How would you calculate the wave length from here? Ok, using de Broglie's relation we have $p = h/\lambda_e$ ...
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0answers
34 views

why do everything tend to be stable? [duplicate]

Whenever I ask'why does a proton attract electron?' People say that 'because they are oppositely charged' But I want to know why do opposite Charges attract each other and tend to become neutralised? ...
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1answer
19 views

What does “touching” mean in the context of charge by conduction in electrostatics?

So in our physics class today, we had a demonstration involving a charged rod and a neutral ball attached to a string (a physical pendulum). At first, when the rod was placed near the ball, the ball ...
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2answers
73 views

Flow of electrons in electric current

In an electric circuit, how does the excitation of the free electrons to higher energy levels translate into net forward motion of the electrons to the positive terminal? My concept of electrons ...
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3answers
65 views

Don't electrons have discrete energy levels in semiconductors?

I am having a hard time understanding the relation between the fermi distribution of electrons in a semiconductor, and the fact the electron energy states are discrete. The fermi distribution is ...
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24 views

Superimposed hydrogen electron states

I have been following an Edx.org course on Quantum Computing. The Prof. has started with a Hydrogen atom qubit, assuming that the electron can only be in the ground state and the first excited state. ...
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4answers
93 views

What would happen if two electrons fuse?

Two electrons repel each other naturally; however, if protons can be forced to fuse, can electrons technically fuse too? What would be the product if two electrons fuse?
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1answer
23 views

What is the positive charge in a capacitor made of?

A capacitor is a pair of conductors separated by an insulator. When it gets charged we have negative charges in one of the plates and positive charges in the other. Negative charges are electrons but ...
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1answer
79 views

How do electrons distribute themselves along a wire attached to one pole of a battery?

Let's assume we have an electrochemical cell, like an AA battery. We attach a long straight wire to the negative terminus of the battery, the other end of the wire extends right away from the battery ...
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0answers
33 views

How does electron excitation work for the Bohr model with non hydrogen atoms?

I've seen a lot of explanations of electron excitation by photons in the Bohr model but they all use a hydrogen atom which only has one electron. How does the excitation work for atoms with more ...
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1answer
42 views

In the stern-Gerlach experiement how do we know that the magnets don't change orientation of the electrons to up or down?

I watched this video: https://www.youtube.com/watch?v=rg4Fnag4V-E Say the electron's north pole started off 60 degrees from the south pole, since the electron has little mass wouldn't that make it ...
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1answer
1k views

Why does a gold leaf appear blue if made very thin?

Is this to do with excitation of electrons and emission of photons? Or is it more to do with the structure of the gold I.e. Only small wavelengths being able to pass through gaps between atoms? EDIT: ...
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3answers
69 views

What evidence is there for quantum leaps?

I find this very strange that an electron can 'teleport' from one energy level to another. So what evidence suggests this?
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3answers
430 views

How much energy is needed to create an electron?

I know how to calculate the electrostatic energy of a sphere (it has a well defined radius). But how can I calculate the electrostatic energy of an electron as it is a point particle? By electrostatic ...
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1answer
50 views

Why do electron and hole mobilities decrease with temperature?

From page 35 of "Microelectronics" by Millman Grabel Mobility $\mu$ decreases with temperature because more carriers are present and these carriers are more energetic at higher temperatures. ...
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1answer
68 views

electron-gas theory of a metal (drude model) - intuition

I'm back to studying "Microelectronics" by Millman & Grabel (2nd ed.). The book makes some references to the electron-gas theory, and I found out to have some problems with my intuition. At each ...
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0answers
42 views

Can photons travel through space independent of time?

I read an article about advanced photons and they stated that photons traveled back in time to hit an electron. Can photons really travel back in time and if so, how?
6
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1answer
88 views

Is the electromagnetic mass real?

In his Lectures on Physics vol II Ch.28-2 Feynman calculates the field momentum of a moving charged sphere with charge $q$, radius $a$ and velocity $\mathbf{v}$. He finds that the total momentum in ...
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1answer
26 views

Is it possible for the phase of electric charge to change over large general relativistic distances?

Jackson provides examples of how magnetic charge and electric charge form together to create complex charge, \begin{align} \rho = \rho_e+i\rho_m \end{align} which gives rise to the complex faraday ...
3
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1answer
107 views

What specifically is incorrect about the Dirac Sea interpretation?

So taking the square root of $E^2 = (m_oc^2)^2 + p^2c^2$ yields two solutions. The Dirac Sea treats the negative solution as an infinite space of electrons with negative energy. All the observable ...
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29 views

Density functional theory and partial charge transfer

When density functional theory is used to simulate a molecule adsorbed on a surface, it turns out that due to their interaction, a fraction of an electron is transferred from the surface to the ...
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1answer
39 views

Is electron interference because of energy transformation from wave to particle and vice versa?

I read about electron interference that in presence of photons there are no fringes formed but in its absence fringe patterns are formed. Can it be explained like this. An electron travels free as a ...
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0answers
13 views

Does illuminating a conductor with light energy less than its workfunction change the measured conductivity?

For example, does the light absorbed in an exposed metal wire increase the average velocity of the electrons, hence increasing mobility and conductance?
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1answer
85 views

Why can't the electron enter the nucleus?

Actually, there exists an attractive force between an electron and the protons inside the nucleus, but the electron cannot be attracted towards the nucleus! What force balances that attractive force? ...
3
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1answer
73 views

In how many possible ways can a photon be emitted?

I am currently studying atomic physics, and I encountered the question above. I am posting this question because I can't afford to move on with even the tiniest bit of uncertainty in my understanding ...
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2answers
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Do we really not know why atoms 'decide' to produce a photon?

I was watching the Cosmos documentary where Neil deGrasse Tyson explained how certain energy photons get absorbed by an atom, which causes the electrons of that atom to climb into a higher energy ...