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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Diagonalizing the Hamiltonian of the two-site Hubbard model

The Hamiltonian for the two-site Hubbard model is as follows: $H = - t \sum_{\sigma = \uparrow, \downarrow} (c_{1\sigma}^{\dagger} c_{2\sigma} + \text{h.c.}) + U ...
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16 views

In the photoelectric effect, what happens to the electron if the work function is too low?

I know that no electrons will be emitted from the atom if the threshold is not reached, but my professor is asking us what happens to an electron in this scenario. I asked if the electron would just ...
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1answer
61 views

What do the batteries actually do to the electrons?

I am plagued by this simple question that what force exactly causes the motion of an electron in the middle of a lattice of electrons of a wire? a. Is it an electric field created inside a wire due to ...
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4answers
595 views

Which formula for the de Broglie wavelength of an electron is correct?

So, I have my exams in physics in a week, and upon reviewing I was confused by the explanation of de Broglie wavelength of electrons in my book. Firstly, they stated that the equation was: $\lambda = ...
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1answer
34 views

What determines the color of photon that is emitted from an exited atom?

I understand the principle of how light is emitted from an atom. What I don't know is why neon atom is red and copper is green when exited? Is is the distance between the electron to protons or the ...
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10 views

What is meant by control over electron in the definition of oxidation number

What is meant by control over electron in the definition of oxidation number
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1answer
30 views

How do I determent the radius and the viscosity of air on an oil drop falling? (Millikan's Oil Drop Experiment)

I bought this article with the intentions of learning how to do the calculations in Millikan's oil drop experiment. ...
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2answers
64 views

Is the conservation of angular momentum violated in electron jumps from one orbital to another?

I don't really know any quantum mechanics. But in our class, we were introduced to Bohr's model of the atom with his postulate that the angular momentum of an electron in the $n$-th orbit is ...
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1answer
98 views
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Thomson scattering cross section: free electrons vs atoms

I am trying to find a reference for the Thomson scattering cross section difference between free electrons and atoms. I have always assumed that free electrons have a higher cross sections, but I can ...
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1answer
54 views

Can electrons escape a black hole?

Assuming that when an electron that changes energy states in an atom, and moves to a different orbit around the nucleus, but does not move through the space between orbits when it changes states, an ...
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1answer
26 views

Is it possible to measure the spin of an electron without moving it?

I know that the position and spin operators commute, so it is theoretically possible. What I want to know is, what experiments currently exist that achieve this?
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1answer
52 views

Why are electrons negetively charged? [duplicate]

Why have we assigned a negative charge to electrons (and positive for protons)? I feel it would be easier if electrons were positive (thereby, protons negative)- electrons would flow in the direction ...
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4answers
56 views

Electrons moving in a simple circuit with a battery and a light bulb

I believe my understanding of electric currents is flawed and want some help to clear up a few things. I'm not looking for a precise scientific understanding, but to understand the basics. I'll try to ...
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0answers
24 views

Can orbital angular momentum of an electron be changed?

In a lab at my university they are working on a project that deals with changing the "net magnetization" of a material by "flipping" the spins on some electrons. Is orbital angular momentum not ...
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1answer
34 views

is there explicit eqution between radiation electromagnetic wave and accelerator a charge that has curve moving path?

i had a basis question i read a rule in electromagnetic when a charge is moving and it has accelerator it will emit electromagnetic wave. now i want to find a explicit equation that describe this rule ...
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1answer
41 views

Why does a magnet loose magnetic strength when heated?

Magnet manufacturing companies, for example Dexter Magnetic Technologies do not hesitate to explain the effects of heat upon magnets - citing how it degenerates the magnetic properties with levels of ...
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1answer
39 views

One particle infinite manifestation universe [closed]

I know how non-intuitive everything related to quantum physics is and I was thinking on some very unintuitive things like John Wheeler one electron universe theory ...
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1answer
40 views

Wavefunction of a system of particles

A three-dimensional volume $V$ contains a certain number $N$ of electrons and they can't escape the volume $V$. Assume for simplicity that the potential $\mathcal{V}(\mathbf{r})$ is zero in all the ...
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25 views

For two electron that moving parallel,can we using this equation for Electric Field and Magnetic Field?

i suppose we have two electron and they are moving parallel,please see picture: my question is can we use this this equation for it? Griffiths' Introduction to electrodynamics): $$\vec E(\vec ...
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27 views

How can absorbtion of a photon in an atom take place? [duplicate]

I will come back to a question posed here and the comment given by John Rennie: If the photon energy doesn't match an allowed transition energy it won't be absorbed and won't excite any transition. ...
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1answer
17 views

How does electricity travel through a set of resistors arranged parallel to each other? [duplicate]

For calculating net resistance in a combination of parallel resistors we use 1/R=1/r1+1/r2+1/r3....but electricity must travel through least resistance. Then how does this relation come in use? I am ...
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7 views

What's the difference between vibrational relaxation and internal conversion?

According to the following diagram, an excited state can dissipate via vibrational relaxation or internal conversion. Aren't they the same thing? (source: Barltrop and Coyle, Principles of ...
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2answers
62 views

Cocepts regarding BCS Theory of superconductivity and Cooper pair

I have a little conceptual doubt about the BCS theory of superconductivity. A visual model of the Cooper pair attraction has a passing electron which attracts the lattice, causing a slight ripple ...
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1answer
36 views

Why is it said that electric current always flow from higher potential to lower potential?

Why is it said that electric current always flow from higher potential to lower potential? It is said that current flows from positive terminal to negative terminal, but it is actually the negative ...
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1answer
40 views

Loss when transfering electrial energy

Let's say we want to transfer a given amount of electrical energy $E$. We could do this with a voltage of $100\,\rm{V}$, but it's better to transform the voltage to $1000\,\rm{V}$, hence the loss of ...
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1answer
24 views

What determines photoelectric yield

Is there any difference between the photoelectric yield of different metals apart from the threshold wavelength? To be more clear: Will metals with the same work function emit the same amount of ...
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1answer
35 views

Photoelectric effect on charged plate

As far as I know, to observe the photoelectric effect, one has to expose a metal surface to high-energy radiation. But what happens if the surface has a surplus of electrons? What is the energy needed ...
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2answers
31 views

Photoelectric effect and wave particle duality

In a vacuum, if electrons are accelerated by a certain voltage, giving the electrons a specific de Broglie wavelength and were incident on a piece of metal, providing the wavelength was roughly the ...
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2answers
27 views

Energy of electrons in wire

The Drude Model helped me quite a lot to visualize how current could flow in a circuit. However, there is still a point that I cannot grasp in the explanation given by some people when they talk about ...
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3answers
93 views

Why electrons flow through a wire connected to a battery?

I would like to know why does electrons flow through a wire connected to a battery as said in AC/DC: What's the Difference?.It tells that "the electrons that are stripped from the carbon electrode is ...
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2answers
106 views

Batteries Do Not Supply Electrons?

I've read that a battery does not supply electrons, it establishes the electric field that exerts force on the electrons in the wires. This makes total sense to me for AC, but not for DC. The way I ...
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3answers
423 views

Why are electrons treated classically in cyclotron measurements?

As I understand , systems having large angular momenta relative to the planck constant (limit of large quantum numbers, e.g. $J/\hbar \to \infty$), can be treated as classical systems. Now in the case ...
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3answers
54 views

Can electrons emit light when they are independent? [duplicate]

If an electron is independent, it is an individual electron, i.e. not in the orbit of the atom. Is it able to emit light or does the orbit have to do with the production of light?
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3answers
294 views

Quantum mechanics of the electron in an atom vs. Gryzinski's free-fall atomic model [closed]

According to Heisenberg's Principle of uncertainty, you can not know the place and speed of a particle, at the same time. You only have probabilities of the estimate values. These probabilities forms ...
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1answer
39 views

What is the reason for extremely high speed of electric current?

I know that electric current is the flow of electrons but electrons have a very slow drift speed (about 2mm/s). How is it that electric current reaches its destination at almost the speed of light?
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3answers
97 views

Can particles at rest have wave nature?

Can particles have wave nature even when they are at rest? I think this is possible due to the formation of standing waves
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1answer
30 views

Thermionic emission

I have a pretty basic question regarding the beam of electrons as a result of thermionic emission. In an electron gun, the emitted electrons from the cathode become incident at a point on the other ...
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1answer
74 views

“Why electrons don't fall into nucleus”simple explanation needed [duplicate]

Am studying in 8th grade and I studied electrostatic force which says opposite charge attracts and same charges repel But in an atom electron is just situated above the proton and it doesn't ...
2
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0answers
39 views

Is the spin of an electron based on its direction of angular momentum? [duplicate]

Is the spin of an electron based on its direction of angular momentum? Is it based on the right hand rule of angular momentum? Does Spin up means that the electron is spinning anti-clockwise and spin ...
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1answer
37 views

Can the electron go below ground state due to the Zeeman effect?

I've read that the Zeeman effect can cause a single allowed energy level to split into two, one of which is higher in energy by some value \Delta E'. The other level is shifted down by the same ...
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0answers
21 views

What makes the thermal insulation materials differ from normal ones?

Is free electrons are playing a critical part? If the answer is yes, then what would happen if I use a positively charged metal without free electrons to transmit heat?
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2answers
80 views

Thought process [closed]

Voltage = Energy/ Charge If voltage comes out of the negative terminal through a wire to do the powering and then end up at the positive terminal, then what is it that comes out the positive ...
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1answer
124 views

How does the electrons' magnetic dipole moment get influenced when electrons are moving through a magnetic field?

How does the electrons' magnetic dipole moment get influenced when electrons are moving through a magnetic field? How does the electrons' intrinsic spin influence the direction of the electrons' ...
2
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3answers
70 views

How can a parallel circuit work? [duplicate]

The electrons always takes the easiest way in a circuit, right? So in a parallel circuit, why does the electrons flow through all parts of the circuit and not just the one with the least resistance?
3
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0answers
20 views

Obtaining a Positive Hall Coefficient for Electrons Near the Top of a Valence Band

Using a Drude model of charge carriers with a charge $q$ and a mass $m$ (which I allow to take either sign at this stage) in a sample with an applied electric field $\mathbf{E}$ and magnetic field ...
3
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2answers
71 views

Nearly Free Electron Model and the Reduced Zone Scheme

When for example studying the vibrational modes of a one dimensional diatomic chain we find that the dispersion relation $\omega(k)$ is periodic in the one dimensional reciprocal lattice vector ...
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1answer
53 views

Does temperature affect to movement of electrons?

Does temperature affect to the movement of the electrons circulating the core of an atom? Do they move faster if temperature increases?
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2answers
69 views

The temperature of an electron

Does an electron have a temperature, if so, what is it? Imagine an electron (Ke = 1 eV) in a tube at room temperature (300 K) what is its temperature? Imagine now same electron in space (3 K) ...
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1answer
46 views

AC Electricity as a Simple Harmonic Oscillator

Can the net motion of electrons in an AC circuit be considered an example of simple harmonic oscillation. Furthermore, how can the general formulae of SHM be adapted to suit a scenario of an AC ...
3
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2answers
119 views

Photon absorption by atoms vs compton scattering

In compton scattering, a photon may deliver only some of its energy to an electron. But when dealing with photon electron interaction in an atom, it's all or nothing. Why the difference? Also, ...