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.

Filter by
Sorted by
Tagged with
1
vote
1answer
159 views

Electrons of conductors Free? [duplicate]

Are electrons of any conductor really free ? I mean are they always already moving or do they move only when electrostatic field of some sort is applied across them. I suppose if they were always ...
1
vote
0answers
87 views

Spin-orbit coupling in itinerant electron systems

Itinerant electron systems are, e.g., metals. The electrons are not anymore localised at the atomic nucleus, but they behave as Bloch waves, which have a non-neglecting probability of travelling ...
1
vote
4answers
213 views

Can a positron decay without encountering an electron?

All the decays I read about involve electron - positron annihilation.
1
vote
3answers
167 views

The model of photon scattering, is actually about a complete absorbtion?

I was wondering about the things like Compton scattering. As I understand, it is an inelastic scattering of photon on free electron. Inelastic means, that photon changes it's angle and frequency. As ...
1
vote
2answers
467 views

Possible inconsistency in Bohr atom model [closed]

It is well known that Bohr model is not totally right. But I recently discovered a very curious inconsistency (if I am right) which I haven't seen explained anywhere. The first postulate of Bohr ...
1
vote
2answers
1k views

Why are electron wavefunctions standing waves?

How can I convince myself that wavefunctions of electrons on molecular orbitals are indeed standing waves? Is it a consequence of the fact that electrons don't drift away from the molecule? In other ...
1
vote
2answers
994 views

Electrons on Stern–Gerlach experiment

My questions about spin and negative charge of electrons. Stern-Gerlach experiment is very famous in order to find spin of electron. this video created by paris-sud university really well-explained on ...
1
vote
2answers
816 views

Does charge of a metal charged by induction determine by which ends of the metal is grounded to?

Does charge of a metal charged by induction determine by which part of the metal is ground to? I draw a diagram to make it simple to understand: Right diagram: When ground is touched with the ...
1
vote
0answers
67 views

Free (unbound, so not bound to a nucleus) accelerated electron cannot emit/absorb a real photon?

I have read these questions: Can a free electron absorb a virtual photon even though it cannot absorb an ordinary photon? Where Michael Seifert says: It is entirely possible for a real electron ...
0
votes
1answer
86 views

what the explicit formula magnetic field a electron that moving on the curve path?

,hi,we suppose ,we have a single electron that moving on a curve path,the velocity is v (it is variable),the path moving is a curve not direct path.i saw maxwell equation my question is ,is there a ...
0
votes
1answer
52 views

How do electrons exit LEDs? Aren't they in the valence energy state?

If a conducting electron reduces to the valence band in an LED, where does it get the energy to go back to the conductance band upon leaving the diode so current can flow? I'm confused as to how ...
0
votes
1answer
163 views

Real QM cause of magnetic dipole moment

I have read these questions: Relation between magnetic moment and angular momentum -- classic theory Why is the electron magnetic moment always parallel to the spin for an electron? Does a magnetic ...
0
votes
1answer
36 views

Electrical neutrality in photoelectric effect

In photo electric effect ,if electrons escape, shouldn't that leave the metal positively charged ??. How does it maintain its electrical neutrality ? And if it doesn't , shouldn't the work function ...
0
votes
2answers
69 views

What is the admissible range of sizes or scales for double slit experiments?

Sometimes, the slits are in the range of nanometers, but I often bump into comments saying you can try this at home with lasers and polarized glass. Recently, I even found clearly macroscopic pictures ...
0
votes
1answer
178 views

Did Feynman ever solve the problem of the difference between bare mass and self-energy of the electron?

The question had to do with the idea that space was filled with particles and that electrons could only exist in specific locations, and same with positrons in the "holes." But if the electron has ...
0
votes
1answer
67 views

Charge density of turning object

A charged disk or sphere will create currents around its turning axis if a rotation is added. The total current can then be calculated by adding all concentric currents together. Every current (I take ...
0
votes
2answers
542 views

How much energy is stored in the charge on each electron?

The energy of electron formation becomes mass, charge, spin and momentum. How much becomes the charge? We know how much becomes mass: E = mc^2. What is the equation for the charge?
0
votes
1answer
1k views

positive charge , current and electron flow in a simple circuit …confusion [duplicate]

my question is that in a simple circuit one wire attached with battery cell ,and then electrons start flowing from lower potential to higher and as we know in metal wire only electron is the thing ...
0
votes
1answer
285 views

Electricity: speed of electron flow

It might seem a silly question but the other day I was talking to some friends and we came up with this question : When you plug your charger into the network, you are getting the electric potential ...
0
votes
1answer
164 views

How will open-circuit voltage affect the Fermi Level Difference

The circumstances of my question consists of this: I have two materials, copper and cesium, and they are sandwiched together with a layer of cesium in the middle. It is connected only on a single side ...
0
votes
2answers
944 views

Why is the charge of a proton positive? [duplicate]

Is there a reason that a proton has a positive charge while an electron has a negative charge? Are these just names that were given to the charges or was there a reason for making a proton have a ...
0
votes
3answers
515 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 ...
0
votes
2answers
619 views

Is the electron magnetic moment responsible for the Lorentz force?

My question about the sum of the electrons' magnetic moments in a wire(What is the sum of the electrons' magnetic moments in a wire?) had an answer which disappeared later. The answer was - if I ...
0
votes
1answer
114 views

Are the electrons spin and his magnetic dipole moment unambiguously connected?

Is the angle between the spin orientation and the magnetic dipole orientation for all electrons and under all circumstances the same?
0
votes
1answer
4k views

Definition of Free Electrons and Mobile Charges?

Could someone please give me a good definition of the following electric terms? Despite what searching I have done, I have not come across a definition that I have found clear for me to understand: ...
0
votes
2answers
809 views

Why bremsstrahlung occurs only with the nuclei? Why not with the electrons?

In many books I read that bremsstrahlung effect (for e+) only occur when the electron goes near the atomic nuclei. Why is not possible when cross near an atomic electron? Thanks,
0
votes
2answers
130 views

Discrete energy levels of electrons in isolated atom

My question is a duplicate of this. Please consider the equation $\nabla^2\psi + (2m/\hbar^2)[E-V]\psi=0$ (1) Potential of electron revolving hydrogen atom is given as $V=\frac{-e}{4\pi\...
0
votes
1answer
485 views

Fermi Dirac distribution and degenerate energy states

In Quantum Mechanics and in semiconductor materials, the number of electrons $N$ in conduction band is usually computed as follows: $$N = \int_{E_c}^{+\infty} g_c(E)f(E)dE$$ where $g_c(E)$ is the ...
0
votes
1answer
235 views

Can we generate electric current by injecting electrons into a copper panel

Suppose I take a vacuum tube and accelerate electrons in it by electric fields then collide it on a copper plate. Will the electrons then go inside it and generate an electric current by putting a ...
0
votes
1answer
88 views

Can an electron absorb a photon even if it exceeds the energy required for the electron to jump up an energy level?

To clarify my question, consider the hydrogen atom. An electron on the ground state needs 10.2 eV to be excited to the second state (first excited state). If a photon with less than 10.2 eV strikes ...
0
votes
3answers
2k views

Couldn't we measure electrons with good enough technology? [duplicate]

I am a bit confused about the Heisenberg's Uncertainty Principle - just read about it in How to Teach Physics to Your Dog, by Chad Orzel. He states that the reason electrons can't be measured is ...
0
votes
1answer
78 views

Can an electron steal speed or energy from the nucleus?

In classical mechanics, there is a famous effect called Sling-shot effect (the link will support a demonstration), by which the satellite orbiting the huge planet will steal some kinetic energy from ...
-1
votes
1answer
72 views

Why motion of a charged particle experences perpendicular motion in a magnetic field? Physical answer please

I understand fleming's left hand rule. But why moving charged particle is deflected? Due to the magnetic field generated by charged particle and resultant direction of that mag. field and applied ...
-2
votes
1answer
315 views

In electron-positron annihilation, why is photon exchange dominant at energies below the Z-resonance?

In a plot of the Z resonance from e+ e- collisions, why is photon exchange dominant below the center of mass energy below the Z peak?