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In classical electrodynamics, assuming a point charge to be having a finite charge, the net electrostatic self energy carried by it is given by $$ Self Energy = 1/2 \int E^2 dV$$ Upon performing the intergral in three dimensions, since the electric field of a point charge diverges at the origin, therefore the rest mass by the virtue of the electrostatic ...


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It sounds like you're asking "If two conductive materials are brought in contact, and one of them is electrically neutral, and one is positively charged, which direction will charge flow?" If that is indeed your question, then the answer is that negative charges (electrons) will flow from the neutral object to the positive object until they are at the same ...


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The Kaluza-Klein equations of motion (the geodesic equations) for a particle moving in the 5D spacetime contain the equations of motion of a particle in 4D spacetime under influence of electromagnetism if and only if one identifies $p^5 = mU^5 = \frac{1}{\sqrt{G}}cq$, i.e. relates the momentum in the fifth dimension $p^5$ to electric charge $q$. (And yes, ...


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In electrostatics, we generally assume our conductors to be ideal. This indirectly assumes that charges have free mobility inside the conductor. You must remember that a system is more stable the lower its energy is. A system of free charges always tries to assume a configuration in which its potential is the lowest. (This configuration is achieved because ...


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q1 and q2 induce charges of the same magnitude and of the opposite sign on the surface of the spherical cavities. This in turn means that on the outside surface of the sphere there are charges induced of the same magnitude and the same sign as charges q1 and q2. These charges are distributed on the outside surface of the spherical conductor. That is there ...


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This is too long for a comment. From Wikipedia In the most recent CODATA adjustments, the elementary charge is not an independently defined quantity. Instead, a value is derived from the relation $$e^2 = \frac{2h \alpha}{\mu_0 c} = 2h \alpha \epsilon_0 c$$ where $h$ is the Planck constant, $α$ is the fine structure constant, $μ_0$ is the ...


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The naive reasoning which leads to the conclusion that charges $Q_1$ and $Q_2$ of two touching conducting spheres with radii $R_1$ and $R_2$ are related by the relation $Q_1 = Q_2\frac{R_1}{R_2}$ is wrong. This formula holds only when the distance between the spheres $L$ is large compared to $R1$ and $R_2$, $L\gg R_1,R_2$, and the spheres are connected by a ...


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You are correct, electric current consists of electrons travelling from one place to another. Some materials conduct electricity better than others. Copper is one of the best and that's why our conductors are usually made of copper. Aluminium is also very good (so is silver) and high-voltage cables are usually made of aluminium. However, everything conducts ...


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The net effect of the charging process is the movement of electron from one plate which then has a net positive charge to the other plate which then has a net negative charge. The battery facilitates this by creating an electric field in the wires and it is this electric field which applies forces on the electrons which makes them move. The movement of ...


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I think you use "relative vs absolute" to mean "distinguishable vs undetermined". If this is the case, we could say it is a possibility that yes, the charge of neutrino is undetermined (relative). This is because having a charge, is physics jargon for "susceptible of certain kind of interaction". Thus neutrinos have no electric charge (do not "feel" ...


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It all depends by what you mean by the word "flow". Let the charged body which is assumed to be a conductor produce an E-field. In a conductor which has mobile charge carriers then the charges can be made to flow within a conducting body which has no net charge. If you subject an uncharged conducting body to an external E-field then the mobile charge ...


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The direction is correct, just note that you can write $$ \frac{\partial^2\phi}{\partial x^2} = - \beta^2\phi $$ and $$ \frac{\partial^2\phi}{\partial y^2} = \beta^2\cdot\left( \phi -\frac{\rho_0}{\epsilon_0\beta^2}\cos{\beta x}\right) $$ This can ease the calculations. The result you obtain is an oscillating potential in $x$, not depending on $y$. The ...


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Look if you substitute the boundary conditions in the given solution it will be identically satisfied, so you don't need them since those were used in the derivation of the given solution. So you have found the charge density and this should be satisfactory, though the final result should be: $$ \rho=-\frac{\rho_0}{\epsilon_0}\cos\beta x , $$ as pointed out ...


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The effects of gravity are really only observable to us on a macroscopic (large) scale. When a large enough number of (perfectly neutral) Hydrogen atoms come together they will gravitate towards each other. That sets things in motion for the Hydrogen to heat up. Once they reach a high enough temperature and density, they will ionize and the protons can ...


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One electron-volt $=1.6 \times 10^{-19} joules$ and is a unit of energy that is equal to the energy acquired by an electron falling across a 1 volt potential difference. The particle (neutrino) doesn't need a charge to have some energy. Instead of expressing the mass of a particle in kg, we can express it as $mc^2$ which is an energy (joules or eV... your ...


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Although the eV is defined with respect to a particle of unit charge (an electron) in an electric field, it is simply a unit of energy. There are simple relations between thr eV and everyday units of energy, such as the Joule or calorie. Thus energies of all sorts of things, in fact any energy, can be expressed in eV, even if it has nothing whatsoever to ...


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In quantum field theory, particles are simply excitations of fields. And interactions are determined by symmetry in an extremely elegant way, see gauge principle. Symmetry is the central concept in fundamental physics. Except that it determines the interaction, it can be also used to classify particles. For instance the spin of particles is characterized by ...


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On the face of it, the answer is "nothing will happen". However, if you bring the surfaces close enough together, you may find that electron affinity between the two is different, in which case electrons may move by a very small amount - in the same way that when atoms react, the resulting molecule may have a dipole moment. The effect would be restricted to ...



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