Questions tagged [electrons]
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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Why is the alpha particle beam in the Rutherford experiment not affected by the electrons?
The force exerted by the nucleus on the alpha particles is electrostatic in nature. So, why does mass has an effect? How do we conclude that the electrons don't effect the alpha particles from the ...
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How does strong nuclear force hold hydrogen vs xenon? does the strong nuclear force have variable distance? [closed]
My understanding is that the strong nuclear force holds the protons and neutrons together as well as the surrounding electrons. give too many electrons and it becomes an unstable isotope due to ...
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The properties of gravity [closed]
We know in the quantum field the play is between electrons. The question is, is gravity made by the gravity of each electrons contracting with each other? I thought this gravity force should be ...
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In inelastic scattering between photons and electrons, how does light only partially transfer energy?
In the case of elastic scattering or absorption between photons and electrons, the incident light is either fully reflected or fully absorbed and hence it either retains its wavelength or ceases to ...
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Nature of force on electron in atom
what is the nature of force on electron in atom .Is it coulombic or electromagnetic force?
As electron is in random motion so we cannot take it as electrostatic force. Please clear my confusion.
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How do we measure an electron's position by shining light on it?
I saw this post which says:
The way you do it is just a simple logic. Imagine a tennis ball and imagine you can't really see it, just like you can't see an electron. So the only way you can see where ...
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Is it really just the electrons which decide the reflection from metals?
uh I'm curious again regarding the theories of reflection.
This is known that
Metals contain free electrons that absorb energy and vibrate when they
come in contact with light. Later, they release ...
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How is it possible to measure the position of electrons? [closed]
How is it possible to measure the position of electrons by shining light on them? I know there will be scattering, but I don't understand how that tells us the position.
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How reversing physics law helps us for electrons in double-slit experiment? [closed]
In the double slit experiment, we got an electron detector screen. Now, there’re 2 cases:
If we don’t have an electron detector screen (which means we don’t “look” at and interfere with electron in ...
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Is increase in current speeding up the electrons or is it just focusing velocities of electrons in the same direction?
Current in a wire is defined as the amount of charge that passes through a cross-section of that wire in a single second. By this definition alone, it is clear that a current relies on the motion of ...
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How do I read a scanning electron microscopy image? [closed]
[! SEM Image Sample 1. Material is Aluminum 6061 with boron carbide and glass particulate]1
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Does the ability of electrons to align their spin to a magnetic field imply that the electron has poles and therefore is not point-like? [duplicate]
We do not know the electron's internal structure, or size. However, I often hear people confidently state that the electron is point-like. Yet, given that it can align its spin based on magnetic ...
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Could the energy levels of electrons in atomic shells be an origin crossing? [closed]
If I have a sinusoidal wave on the X or Y plane, it will only be visible on the Z plane when the x or the Y coordinate is at zero.
If I go to 4-space with an added dimension "w", the same ...
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Why should there be a gas in a cathode ray tube?
Is it necessary to have a gas in a cathode ray tube? Why?
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How do the electrons in a current-carrying wire move?
How do the electrons in a current-carrying wire move? Do they move in straight line, zig-zag or randomly while attracted to the positive charge? Picture or video examples are welcomed.
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Why is there a repeated root to the Einstein energy-momentum relation?
Using the metric signature $(+---)$, a particle in some reference frame $K$ moves with four-momentum $p^\nu$. In this same frame we may define the spacelike vector $U^\nu$ with the property $U^\nu ...
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Why is the attraction of ions near the surface stronger than the repulsion of electrons? [duplicate]
We consider an electron "Bob" trying to escape from a metal surface as shown (blue circles represent electrons, red circles represent ions). I know that Bob can't leave the metal surface is ...
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The fine structure constant is a function of the electron mass [duplicate]
What is said here goes by itself according to the standard model, but last time I wanted to get a confirmation here I only caught myself a bloody nose (see what Simplicio is telling below, and the ...
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Galvanic cell - when do we get electric potential?
In the galvanic cell in this image (2nd one with salt bridge): Link
Before putting the copper wire into the solution, do the Zn metal electrons have potential energy with respect to Cu2+'s electric ...
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Why do we call high terminal the positive side?
I want to confirm if I understand something correctly.
We call the "high potential terminal" the positive side (cathode).
Though, electrons move from negative to positive. Logically, ...
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Is the fine structure constant a function of electron mass? [closed]
The main statement is: the EM coupling constant is energy dependent, and the fine structure constant (FSS) is the low energy limit. This means that the flow of the coupling constant vanishes when the ...
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Why when not observed in the double slit experiment, do we see light in places we do not see light when observed?
The double slit experiment with a single electron provides a different result when observed and when unobserved. When unobserved we see an interference pattern, and when observed we just see 2 lines. ...
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What force attracts electrons so that they cannot leave the conductor?
When a conductor is in electrostatic equilibrium, as far as I know, the electric field on the surface must be perpendicular to the conductor. This leads to a rather difficult problem for me, if the ...
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Copper wire - how electrons behave?
we know, copper has 1 electron on the last shell(smallest ionization energy).
we also know that in a copper wire (don't imagine copper wire with electricity, imagine no electricity exists), A cubic ...
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Are there other energy bands over the conduction band?
I've found this diagram about the conduction band (https://energyeducation.ca/encyclopedia/Conduction_band):
But are there other energy bands over the conduction band? Or is the electron simply ...
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Energy level photon spectra for different atoms
I'm trying to determine the photon emission wavelength ranges for different atoms.
For hydrogen, it's super simple. We use the $$ E_n = -\frac{13.6}{n^2} $$
Then, if we want to see the wavelength of ...
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How does inner Bremsstrahlung work?
I'm trying to understand inner Bremsstrahlung. I know this applies to beta minus decay, but have a hard time understanding how it works. In the beta decay, electron is emitted from nucleus. I believe ...
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Chemical potential vs Electrostatic potential in semiconductors
In Semiconductor Physics, the bottom of conduction band $E_C$ is treated as the electrostatic potential. This energy level is typically used to express the carrier concentration in terms of the ...
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How can electron diffraction be described using the Schrödinger equation?
Can someone point me to resources where this process is described using the Schrödinger equation? It's not obvious to me how that could be done, as you'd need to define the proper potential.
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Roundness of electrons [duplicate]
I have seen articles online discussing the roundness of electrons. This goes a bit against my understanding of electrons as elementary point like particles. How can a point have a shape? What does ...
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2 Fermions in a 1D infinite potential well
I had a brief question regarding 2 fermions (with spin) in a 1D infinite potential well (going from $-L/2$ to $+L/2$, where $L$ is the width of the well).
To start off with the question, "what ...
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Deacceleration of particles - how does it happen?
When atoms are formed, first nucleus is formed and then, nucleus attracts electrons(we can call them free electrons) and we get an atom.
but in terms of Bremsstrahlung, what happens is:
In the case ...
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Is an electron always in an eigenstate of *some* spin observable?
Is it right to think that an isolated electron is always in an eigenstate of the spin observable along $some$ axis? For instance, even if the electron is not in an eigenstate of $S_x, S_y,$ and $S_z$, ...
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Total spin of Entangled Electrons
If, say, the z-spins of two electrons are maximally entangled (so that their composite state can be given by $|\Psi\rangle = \frac{1}{\sqrt{2}}(|u\rangle|d\rangle + |d\rangle|u\rangle)$, how do you ...
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Why friction as a method of charging is used only for insulators not for conductors?
I was solving a question of electrostatics and it was Friction as a method of charging is used for whom ? I answered both insulator and conductor because friction causes production of heat which in ...
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Uncertainty in position of an electron in a cube
I was solving a question which asked the uncertainty in velocity of an electron trapped in a cube of length x.
Well in the solution they have taken the uncertainty in position to be length of the body ...
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Why do we insist that the electron be a point particle when calculation shows it creates an electrostatic field of infinite energy?
I've heard compelling reasons to think that it is one although why do we assert this in light of the calculation which shows a point particle creates an electrostatic field of infinite energy (see e.g....
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Given $\rm V=J/C$, is it better to think of the Coulombs as moving charge, or moving electrons?
I have been confused by how voltage is measured in joules per coulomb, until I thought of it in the context that the coulombs aren't measuring charge, but instead are measuring how many electrons are ...
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Value of potential difference between two charged plates
I am currently practicing Physics questions in basic electrostatics and I am confused about why my teacher is randomly assigning V (potential energy) as 0 in random sides of two parallel plates (where ...
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How does light interact with atoms?
I've read this answer regarding the difference between mere reflection and absorption followed by emission and I am struggling to understand some concepts. To begin with, we have some matter-light ...
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Does de Broglie equation give the exact/true wavelength of electrons?
Im talking about the de Broglie equation-
wavelength $\lambda =\frac{ h} {p}$
I studied a bit about Davisson-Germer experiment that provided conclusive evidence for wave nature of electrons and more ...
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Why are cathode rays invisible?
I know its the most basic question, but I do understand that cathode rays are beam of electrons and its not 'light'.
But why can't we see any 'reflected' light from the electron beam i.e if we put (...
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What is stopping us from splitting an electron? [closed]
If we could split an electron, we would probably find new things. So, why don't we shoot a lot of energy at it, and see what happens? I tried looking up what happens, but I got no good answers.
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Do free electrons always interact with any photon they 'contact'?
Do free electrons (plenty of them in space and in stars) scatter every photon they come across?
Free electrons, unlike those in atoms and molecules, don't have specific energy levels after all...
Isn'...
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What does it mean when the $1s$ and $2s$ orbitals overlap?
The shape of the $s$ orbital is spherical. Consequently the $1s$ orbital will be a sphere with nucleus as its center while $2s$ will be a similar but bigger sphere.
Now orbitals represent the space in ...
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How do we know charge is only positive and negative? [duplicate]
Could there be a charge different than that of a proton and that of an electron? Could there be a third type of charge that is not repulsed or attracted by either an electron's charge or a proton's ...
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Missing term in first-order energy of an homogeneous electron gas?
For jellium, the electron-electron interaction energy of a homogeneous electron gas is
$$V=\frac{e^2}{2\mathcal V}\sum_{\sigma\sigma'}\sum_{\mathbf q}\sum_{\mathbf k \mathbf k}\int\mathrm{d}^3\mathbf ...
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Dipole moment operator for many a electrons wave function
From textbooks (such as Optical Spectroscopy of Inorganic, Henderson, 2006) I know that the electric dipole moment operator is defined for one electron as:
$$
\hat{\mu} = e \hat{r}
$$
But then suppose ...
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ProtoElectric Effect: How would this work?
In the 'Photoelectric Effect' setup, if I replace the light source with a 'Proton Gun', What would be the result?
I tried to search around and could shortlist a few possibilities, but am not sure if ...
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Does frequency affect current in Photoelectric effect? [duplicate]
If frequency of light in a photoelectric effect experiment increases (assuming its already enough to ionize the electrons), apparently the current will remain unaffected. This is contradictory to the ...
