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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0answers
24 views
What is the source for magnetic energy? [duplicate]
"The electron around the nucleus is in a quantized energy level and can change it only if an external interaction intervenes." That is OK but when there is a magnet, it has energy of attracting iron ...
2
votes
2answers
67 views
Empirical bound on sum of electron and proton charge
Followup to "Why do electron and proton have the same but opposite electric charge?".
It is argued that even a tiny residual charge would result in huge amounts of electricity in bulk matter, ...
2
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1answer
62 views
A question about how light hits a surface
my question is about how photons travel from a light source and hit an object.
When you look at an object being hit by light the whole surface becomes brighter.
What i'm trying to understand is why ...
0
votes
2answers
678 views
Frequency of an Electron
My question is very simple.
If frequency is defined as the cylces per unit time, Then what is meant by "Frequency of an Electron" ? If the rotation of electron around a nucleus is considered then, ...
0
votes
2answers
87 views
Electron mass changes with website
When particles mass can be changed by changing the website, then how to calculate with confidence?
For example:
Google: electron mass = 9.10938 188 × 10$^-31$ kilograms
Wikipedia: electron mass
...
2
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2answers
243 views
Flow of electrons in a circuit
When the electrons flow in a circuit, so are those the electrons from the battery or are those the electrons of conductor like copper wire, etc..which are flowing in the circuit?
15
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6answers
1k views
What would happen if Large Hadron Collider would collide electrons?
After some reading about the Large Hadron Collider and it's very
impressive instruments to detect and investigate the collision results,
there is a remaining question.
What would happen if the ...
2
votes
1answer
189 views
Positive test charge
Protons have positive charge on them. Protons aren't mobile. So how can a positive test charge move from the negative terminal of a cell to the positive terminal and gain electric potential energy? ...
1
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2answers
156 views
Typical operators in tight binding
Let the tight-binding Hamiltonian be $\sum\limits_{ij} {{t_{ij}}\left| i \right\rangle \left\langle j \right|}$. Where ${\left| i \right\rangle }$ is the atomic orbit at lattice site $i$.
My question ...
2
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1answer
96 views
Does the electromagnetic field “spin”?
Due to electron "spin", a small magnetic field is produced. Maxwell's equations imply that magnetic fields are due to changes in electric fields. Is the magnetic field produced then because the ...
0
votes
1answer
42 views
Regarding “Holes” in bands, and Photons
So from learning Band theory, and PN Junction and such, I've learned that photons are created when "holes" are filled in a band, and this is what can create light (Isn't this how LEDs work?)
Anyways, ...
4
votes
3answers
145 views
Do electrons in multi-electron atoms really have definite angular momenta?
Since the mutual repulsion term between electrons orbiting the same nucleus does not commute with either electron's angular momentum operator (but only with their sum), I'd assume that the electrons ...
6
votes
2answers
154 views
Do the energy levels of electron orbitals change relativistically?
When an electron emits a photon from changing energy levels, the frequency of the photon depends on the difference between the energy levels.
But if someone is moving with respect to the atom, the ...
5
votes
1answer
136 views
What happens to 5 electrons on a sphere?
Let's suppose we put 5 electrons on a perfectly conducting (no resistance at all) sphere.
There's no equilibrium configuration with 5 (though there is with 2, 3, 4 or 6). So will they keep moving on ...
3
votes
0answers
36 views
Special conditions at layer F2 ionosphere
I saw this graph about the electrons density in different altitudes and difference between night and day, the difference between the 2 electron densities (day and night) decreases till 300 Km (F2 ...
0
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0answers
41 views
frequency of the photon [closed]
If an electron is accelerated within a cathode ray tube using a voltage difference of 3000 V then what is the maximal frequency for the photon that can be radiated from the electron ?
0
votes
1answer
184 views
Elastic collisions in Franck-Hertz experiment
Looking at a Franck-Hertz experimental setup, and given a potential difference such as $4.0\ V$ which is too small to excite out the first electron orbital, the electrons moving through the tube will ...
-3
votes
2answers
128 views
Energy source of electrons?
I am aware that electrons are moving in an empty space so basically there is no friction to slow it down and its velocity stays the same. However where did the electron get its energy from in the ...
1
vote
3answers
244 views
What does a subatomic charge actually mean?
I was recently reading a popular science book called The Canon - The Beautiful Basics of Science by Natalie Angier, and it talks about subatomic particles like protons, neutrons and electrons in ...
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2answers
142 views
How does an electrical field really work?
A little bit of background information: I'm planning to write a little booklet or web page about CPU/computer architecture, basically for my own education, because we didn't cover it in depth in ...
3
votes
3answers
493 views
Where do electrons in electricity come from?
Where do the electrons come from when an electric generator is making electricity? Is from the air? Would a generator work in a vacuum? Electrons have mass so where would they be pulled from if ...
4
votes
1answer
211 views
How many states can a n qubit quantum computer store?
A classical computer composed of '0' or '1' transistors stores $2^n$ states.
Is it true that a quantum computer composed of '0' or '1' or '0 & 1' qubits stores $3^n$ states?
0
votes
0answers
37 views
Working out the electron mobility from the transfer rate (1/s)
I have an electric field value for a uniform structure through which an electron travels. Given that I've calculated a transfer rate (frequency) for the electron when it goes from one molecule to the ...
2
votes
1answer
91 views
Working out the electric field from applied energy
I have created a simulation of one electron bouncing through a 3D mesh of molecules. The electron hopping is determined by a calculation of electron transfer rate using the Marcus equation (a result ...
4
votes
4answers
552 views
How do electrons jump orbitals?
My question isn't how they receive the energy to jump, but why. When someone views an element's emission spectrum, we see a line spectrum which proves that they don't exist outside of their orbitals ...
3
votes
0answers
127 views
Electron hopping among molecules - Marcus equation
I'm running out of professors to talk to, and I need to clarify a couple of things for the sake of making a realistic model of electron travel through a mesh.
This is about calculations of electron ...
3
votes
2answers
272 views
How exactly does static discharge work?
Assume I have built up a pretty high charge by rubbing the floor or something. I want to understand these situations:
I almost always get shocked when I touch a metal doorknob with my bare hand.
I ...
2
votes
1answer
69 views
Ejected Electrons with 0 KE?
So I was taught that:
Kinetic Energy (of electron) = Energy (of photon) - Ionization Energy
If E(photon) = IE, then KE=0 of the electron.
What does this physically/theoretically mean?
My current ...
2
votes
3answers
831 views
is it possible to flow current in open circuit?
First , i don't know much about chemistry and physics. I'm just a graphic designer but i have this question in my mind. I'm sorry if this question is too basic and use 'generic' language.
As i know ...
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vote
3answers
93 views
A problem concerning the force between currents or moving electrons
Concerning two identical wires carrying the same current (same direction, speed and magnitude), they will be attracted because of the Ampere force. But when I was in the frame moving with the same ...
0
votes
1answer
213 views
Dipole moment of the electron
I've read that there are some restrictions on the value of a possible intrinsic electric dipole possessed by the electron, but isn't the dipole value dependent on the electron's wavefunction? Assuming ...
0
votes
0answers
87 views
The Deflecting System in a Hot Cathode Ray Tube
In an HCR-Tube, the deflecting system used to deviate the electron beam is made of positively charged plates. How is this justified? If, due to some malfunction, the electron beam deflects from its ...
1
vote
1answer
68 views
How does the specific frequency of EM Radiation relate to displacing electrons from their orbits?
I've only a general grasp on how all this works, so it could be I'm asking this poorly or misunderstanding what happens. With that said:
The energy of EM radiation is a function of its frequency. ...
0
votes
0answers
123 views
Research in Quantum Physics [closed]
I am Suvankar, a student of engienering. My branch is Electrical & Electronics Engineering. Although this is a Physics oriented website, I want to know whether it is possible to do M.Sc. after ...
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1answer
155 views
Why photons are emitted because of changes to electron behavior
Explanations I have read of why photons are emitted from atoms mention electrons being 'excited' to another energy level, and then returning to their base level, releasing a photon. I have also seen ...
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4answers
195 views
Find total energy and momentum of an moving electron in a rest frame
I have an electron moving with speed $u'$ in a frame $S'$ moving with speed $v'$ relative to a rest frame $S$.
How do I find the total energy and momentum of the electron in the rest frame $S$?
I ...
2
votes
2answers
679 views
How many photons can an electron absorb and why?
How many photons can an electron absorb and why?
Can all fundamental particles that can absorb photons absorb the same amount of photons and why?
If we increase the velocity of a fundamental ...
3
votes
3answers
164 views
What if $\gamma$-rays in Electron microscope?
I was referring Electron microscopes and read that the electrons have wavelength way less than that of visible light. But, the question I can't find an answer was that, If gamma radiation has the ...
6
votes
2answers
292 views
Is there a published upper limit on the electron's electric quadrupole moment?
I understand an electric quadrupole moment is forbidden in the standard electron theory. In this paper considering general relativistic corrections (Kerr-Newman metric around the electron), however, ...
2
votes
3answers
169 views
can I move the atom core only?
I was wondering if it is possible to move the atom core and leave behind the electrons. I can imagine that the electrons will follow the core. But what if the speed of the core is almost the same as ...
4
votes
1answer
151 views
Stability of a rotating ring of multiple electrons at relativistic speeds
There was a time when physicists where concerned about electron internal structure. The rotating ring model was one of the proposals to explain how a charge density could become stable against ...
2
votes
1answer
71 views
What does $\psi_j(r_i)$ mean?
I have a mean-field Hamiltonian for N electrons. The mean-field potential felt by electron $i$ at position ${\bf r}_i$ is given by
$V^{(i)}_{int}({\bf r}_i)=\sum_{j\ne i}|\psi_j({\bf r}_i)|^2$
I ...
1
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1answer
227 views
Excess charge on an insulator and conductor
So I was recently wondering what happens to the excess charge when it is placed on an insulator or conductor e.g. rubbing two objects together. I know in the conductor the electrons are free to move ...
0
votes
1answer
134 views
Units in cgs system
How do I find the dimensions of this quantity (in $cgs$)...
$$\frac{4\pi me^2}{h^2n_o^{1/3}}$$
where $m$ is the mass of electron
$e$ is the magnitude of electronic charge
$h$ ...
2
votes
1answer
178 views
Is Fractional quantum Hall effect proof that leptons are composite particles?
The fractional quantum Hall effect (FQHE) is a physical phenomenon in which the Hall conductance of 2D electrons shows precisely quantised plateaus at fractional values. Should this be considered ...
0
votes
0answers
64 views
Converting $q/m_e$ to $C/kg$ [closed]
I was doing some chemistry problems when I came across a question asking to find the charge to mass ratio of an electron in $q/m_e$. Then, it told me to compare what I found to the accepted value, at ...
6
votes
1answer
223 views
Relativistic drift velocity of electrons in a superconductor?
Is there a formula for the effective speed of electron currents inside superconductors?
The formula for normal conductors is:
$$ V = \frac{I}{nAq}$$
I wonder if there are any changes to this ...
0
votes
1answer
102 views
Making or Demonstrating Principle of Electron Microscope
is it possible to either demonstrate the principle or make a SEM ( electron microscope ) at home or lab as an enthusiast??
and how can i start?
2
votes
1answer
337 views
Why is it that protons and electrons have exactly the same but opposite charge? [duplicate]
Possible Duplicate:
Why do electron and proton have the same but opposite electric charge?
Doesn't it seem very curious that one is an elementary particle and the other a subatomic particle ...
0
votes
1answer
154 views
The electron jumps and lets loose photons
Where is the source of the photon.
If the photon propagates from within the electrons transit does this point to some sort of field?
Does the energy come from a boundary being broken in laymens ...
