Electron Definition and 999 Threads

Do the orbitals of electrons change positions within their energy level relative to the nucleus or are they statically "attached" to the nucleus? To try and put this into perspective, would the orbitals of the electrons be like nailing a balloon(orbital) straight to the ball(nucleus) or nailing...

Given that (a) the electrostatic force is inversely proportional to r2 (b) that the electron is (when it is determined) a point (c) that the repulsion for an electron to itself is therefore r=0 (d) that r=0 would naively end up with infinite force What is the way out of this problem? Thanks

I was reading through a paper about the first case of experimentally proving that electron transfer can occur over the length of a bacterial nanowire. The paper mentioned that, previously, electron transfer was only measured across the thickness of the wire. "Thus far, there has been no...

If positive and negative charges attract each other, why don't electrons just stick to the protons?

If you rub two electrically neutral pieces of insulation together, one piece becomes charged and the other piece becomes oppositely charged. Does this transfer of electron depend merely on the electron affinities of the two pieces, or does the conductivity of the two insulations play a part? I...

thankyou to anyone reading this. I am starting honours in physics and have been given the opportunity to do a project that leads to a phd in the condensed matter theory. The guy I will be working with seems to specifically do work around the theory involved in electron microscopes. hes a great...

Hi! I have understood how elements such as Be and Ca, with fully filled 2s orbitals, are not to be considered "noble" because they still have unfilled p orbitals. But I'm having trouble understanding how these elements participate in chemical reactions without having any unpaired electrons. My...

we generally talk about electron current in metals.but when an electron leaves, it leaves a hole in its place. does the hole current really exist in metals?please explain the stuff.

So i have this simple situation where i have an electron beam with a certain kinetic energy, and i have a metal plate connected to the ground, and the electrons hit the plate, now i want to know the voltage of the current in the wire to the ground. Now i know both kinetic energy of the electrons...

Hi All, Does a beam of "low energy/small wavelength" gets refracted when passing from one media to another. Thanks

hi, I just looking for Video on diffraction pattern of Electron, and noticed it produces green color pattern. Earlier in chapter, when cathode ray was discovered, it was mentioned that Green glow was Noticed. What is the reason for this green color?

I'm looking at a program for Monte Carlo simulation of electron trajectory in a matter. When I look at the detected X-ray spectrum, there are two distinct curves, one called "characteristic", the shape of which is peaky. The other is called "background" where the shape is continuous. My...

Is it because the electron has less mass and is a point object that prevents it from falling into the nucleus due to attraction of protons?

Hello, I am studying transport in the free electron gas model and I don't understand how to compute the average of the electron density current. We are given the hamiltonian ## H=\int \psi^\dagger(r,t)(-\frac{\hbar^2\nabla^2}{2m}+e\vec{E}\cdot\vec{r})\psi(r,t)## where the ##psi## operator is...

This may be a naive question but this has been bothering me. I read that electrons having energy above 100 keV are considered as relativistic, on the other hand electron's rest mass is 511 keV. How can a free electron have energy less than its rest mass? What kind of energy implied in saying...

If you place an electron between oppositely charged parallel plates, is it true the the force on it is the same regardless of how far it is from each plate? If so how?

Homework Statement An electron with a speed of 1.1 × 107 m/s moves horizontally into a region where a constant vertical force of 3.2 × 10-16 N acts on it. The mass of the electron is 9.11 × 10-31 kg. Determine the vertical distance the electron is deflected during the time it has moved 34 mm...

Why is/are an electron/electrons a sphere/spheres ? Need the mathematical proof...

Homework Statement How much work is required to stop an electron (m=9.11×10−31kg) which is moving with a speed of 1.40×10^6 m/s ? 2. Homework Equations The Attempt at a Solution E.g a particle has KE=10J. The work that must be done on it to stop it is -10J. So work out the kinetic energy...

How might we construct a state most closely corresponding to the idea of a single electron wave packet as some superposition of Fock states?

U(x,y,z,t)*ψ(x,y,z,t)-(ħ/(2*m))*(d2ψ(x,y,z,t)/dx2+d2ψ(x,y,z,t)/dy2+d2ψ(x,y,z,t)/dz2)=ħ*i*dψ(x,y,z,t)/dt qproton=-qe Schrödinger equation for electron in hydrogen atom (if we consider proton as point charge which is moving at a constant speed vproton→=(vp;x;vp;y;vp;z).) is...

Where from do the electrons in an atom get the energy to keep constantly moving around the nucleus of an atom

If electron can show behaviour of wave in double slit experiment like interference, diffraction, can it pass through fibre optic cables, if it is accelerated with high speed into the cable?

Is there an electric or magnetic field from the electron present in the deconstructive regions of the electron interference pattern?

Not quite sure how to ask this, but here goes: I think I understand how a photon impacting an atom can increase the energy level of an electron in the atom. When I read about "light pressure", I thought, is there a way for, say, a stream of photons to accelerate an atom by continually impacting...

Hi all, I am currently writing a report about superconductors, and am currently reading about how the band gap shows that single electrons are not the charge carriers responsible for superconductivity. However, I was confused when I read that electrons are fermions and as such there are no band...

Hi, is it true that the heavy atoms decaying only by electron capture should have globally a half-life shorter than ligher nuclei (decaying also only by electron capture)? This assumption comes from the fact heavy atoms have inner electron "closer" to their nucleus than the lighter ones and so a...

Spin is an intrinsic property of particles meaning that they have it naturally. Electrons can have either +1/2 spin or -1/2, what dictates that it is one instead of the other?

Hey! I am trying to figure out this one problem. Some help would be appreciated. How can i relate the maximum distance traveled by an electron at a given pressure? So electron is colliding with air molecules. I wonder if there is a formula or derivation which relate maximum penetration and...

Has electron recoil due to photon emission ever been confirmed by experiment? cause I can't find any reference to electron recoil being measured anywhere I look. If it has been measured, what methods do they use?

An electron rest mass in kilograms is calculated from the definition of the Rydberg constant R∞: where α is the fine structure constant and h is simply Plancks constant. Now, assuming the electron has an associated rest energy, Any idea on how this is calculated? I'm assuming using...

Homework Statement An electron is placed in an xy plane where the electric potential depends on x and y as shown in the figure (the potential does not depend on z). The scale of the vertical axes is set byVs = 500 V. In unit-vector notation, what is the electric force on the electron...

Hi, I'm new to the forum, and I am very sorry if this has been asked before. I am Japanese and therefore my English might be a little bit awkward. I want to ask about term symbols and if they can be used to derive electron configuration in lanthanides. First of all, I do not major in Physics...

Is the Abraham-Lorentz force (Also called radiation reaction force) the only recoil experienced by an accelerating charge? Say an electron is accelerating downwards, and that a photon emitted from this electron travels right, perpendicular to the direction of motion of the electron. Does the...

Homework Statement Neutrinos with energy of about ##1 GeV## are measured in an underground detector and compared with simulations of neutrinos produced in the atmosphere. Measured flux of upward going muon neutrinos ##(\nu_\mu + \bar \nu_\mu)## is half compared to simulations while measured...

Just wondering if there's a precise definition of what it means to be an elementary particle. I had assumed it was related to not being able to convert it into multiple "smaller" things, but then a photon is called elementary when it can be converted into smaller energy positrons and electrons.

Hello, At first, I wasn't sure why p-orbitals are shaped as they are. I looked through the posts of others here and it makes some sense now. My understanding is that they are dumbbell shaped because electrons repel from each other and are attracted by the nucleus. Then why is an s-orbital...

I want to ask one question, in physics, we calculated acceleration of electron in a conductor, but according to classical electrodynamics, any charged particle while accelerating looses energy through EM radiations, So does these electrons also emit radiation, if not then please tell me WHY?

This the answer that I have from Chalnoth in my other thread about nuclear fusion inside the sun (or star in main sequence). And after iron burning in the core of massive star, the star explodes and leaves a neutron star (or a black hole) behind. Is producing neutron in P+P reaction chains and...

Standard quantum mechanics text-books discusses Born rule, which states that the probability of finding a particle in a certain region in space is given by $$ |\Psi ({\bf r},t)|^2d^3r $$ Thing is, I never have seen a discussion about how you can actually measure the particle position in a...

Homework Statement Calculate the Q-value for the electron capture beta decay of Kr-81 (Answer in MeV, correct to 6 significant figures) Atomic Masses (amu) Kr-81 = 80.916592(3) Br-81 = 80.916291(3) proton 1.00727647 neutron 1.00866501 electron 0.0005485803...

Does the energy of the electron in a random hydrogen atom is in superposition of all eigenvalues(some value upon measurement) or you will find it most likely in the ground state. Additional clarification: From my reading the textbooks said the electron energy is in superposition, yet the...

What does trigger the phenomenon of an atomic electron losing energy through the issue of a photon? (I know how an atomic electron absorbs light and changes to a more energetic level but I never read an explanation cause-effect of the inverse)

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Hi there, I have a question about the definition of a charge of a free electron. Let's suppose that QED is the true theory of the interactions of charged particles. Presumably the charge on an (effectively) free electron, then, is the charge on an electron in which the electromagnetic...

Okay, I tried searching for this in the forums and didn't really find what I was looking for. So, I'll start a new thread and if anybody has seen this before, feel free to drop a link to an old thread or whatever. Many of our older space probes use/used thermoelectric radioisotope batteries to...

What are the number of states available to the electrons, and what is the difference between the ease of getting electrons to change states considered against the ease with which they change states by themselves? Can you give an example where they change states by themselves?

Hi there, I have a question about the rest mass of an electron. As we all know, the charge of an electron is a function of the energy at which the system is probed. When defining the charge, we typically use as our reference scale the charge measured in Thompson scattering at the orders of...

Just double checking this - I found this formula describing the radius of the path of an ion in a cyclotron: R = sqrt(2*E*m)/(e*B) .. where R is the radius in meters, E is the energy of the particle in joules, m is the mass in kilograms, c is the charge in coulombs, and B is the strength of...