A fundamental and empirical law quantifying the electrostatic force between two charges.

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34 views

How to find the electric field of a charged tube?

Let's say there is a charged tube(cylinder with no top or bottom) with radius $a$, length $l$ and charge $q$ and a point which is collinear with the centre of the charged tube. Anyway, since we can ...
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0answers
14 views

How to calculate the electrostatic force between two dielectric rings of charge?

Let's say there is a dielectric ring of charge with radius $a$ and charge $q_1$. I could calculate the electrostatic force applied on a point charge with charge $q_2$ and which is collinear with the ...
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0answers
19 views

How to ask debunking questions (trying to examine decuity.com claims “Light is an inertial particle not a wave” etc.)? [migrated]

What is the proper format to ask debunking questions without being marked as off-topic, yet be able to step through the entire theory logically? Specifically, I am looking at Wallace Kluck's claim on ...
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0answers
27 views

Can someone help me clarify the Coulomb separation issue mentioned on decuity.com? [on hold]

I am trying to understand what Wallace Kluck is getting at about the coulomb forces on decuity.com He states two minor changes essentially rewrite modern physics - - I see where the charge lines ...
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1answer
42 views

What would happen if charged plates are placed horizontally?

My idea is placing charged conducting plates in such a way that they won't see each others' surfaces unlikely to the typical design of parallel plates. If they are placed like this, would be the force ...
42
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10answers
5k views

Can Maxwell's equations be derived from Coulomb's Law and Special Relativity?

As an exercise I sat down and derived the magnetic field produced by moving charges for a few contrived situations. I started out with Coulomb's Law and Special Relativity. For example, I derived the ...
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1answer
48 views

How to calculate the force between line of charges?

As far as I know Coulomb's law only works for point charges but what if there are not any point charges? For example, let's imagine there are three rectangles with different sizes. First one is 50 cm, ...
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2answers
20 views

Effect of variable permittivity

If I immerse a rod vertically in a liquid with a relative permittivity gradient (the permittivity decreases with depth), will the rod stretch (will the spacing of the atoms in the rod be affected by ...
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1answer
151 views

Does QED provide a closed form for Coulomb logarithms?

The classical models for the integrand as well as the cut-offs in computing the Coulomb logarithm are pretty rough. Does quantum electrodynamics have definite expressions for the quantity ...
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1answer
51 views

The Physics Behind Chemical Bonding

Ok so here's the problem: say I'm a sodium atom. It is 'charged' at +1e. A partner Chlorine atom is flying about, also 'charged' at -1e. According to chemistry (or rather the measurement of the ...
2
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1answer
51 views

Why do we take the value of the constant in Coulomb's law as $\frac{1}{4\pi\varepsilon_0}$? [duplicate]

Why do we take the value of the constant in Coulomb's law as $\frac{1}{4\pi\varepsilon_0}$?
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6answers
594 views

What is the range of the validity of Coulomb's law?

What is the smallest and biggest distance in which Coulomb's law is valid? Please provide a reference to a scientific journal or book. Just saying that this law is valid from this range to that range ...
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0answers
15 views

Is there a simulator for observing the force between two charges comprehensively? [duplicate]

I basically want to observe the electrostatic force between two charges. I want to know if is there a simulator which could both help me to observe and calculate the force between two charges. I ...
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0answers
21 views

Is there a simulator for observing the force between two charges?

I basically want to observe the electrostatic force between two charges. I want to know if is there a simulator which could both help me to observe and calculate the force between two charges. I ...
6
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5answers
204 views

Is Coulomb's law accurate for moving charges?

Can we use Coulomb's law to calculate the force between two charges which are not at rest? If not, what formula should be used to calculate the force? I searched it, but I couldn't find a clear ...
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0answers
80 views

Why does Coulomb's law not hold for fast moving charges?

We all remember calculating the electric force of interaction between a stationary nucleus and a revolving electron using Coulomb's law. The electron in this case is moving. Here's what I think about ...
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1answer
155 views

Classical vs. quantum energy of the hydrogen atom

If I have an electron and a proton and calculate the classical energy which I get by bringing the electron from infinity to the distance of a Bohr radius to the proton, I get 27.2 eV, but the electron ...
2
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2answers
31 views

Electrostatics - Inserting a brass plate between two charges

The question is: if I were to insert a brass plate between two charges, what will happen to the force between the charges? Would it increase, decrease or stay the same? Does the brass plate increase ...
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2answers
108 views

The fundamental equations of electromagnetism

I'd like to know what are the basic equations of electromagnetism, that can be used to formulate all the other laws and equations. Those basic equations I can think of are Maxwell equations, Lorentz ...
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2answers
377 views

Why is there no permittivity-type constant for gravitation?

When I look at electric or magnetic fields, each of them has a constant that defines how a field affects or is affected by a medium. For example, electric fields in vacuum have a permittivity constant ...
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0answers
84 views

Has this approach to Coulomb force/Newton gravity unification ever been published?

Introduction: When toying with gravitational and electromagnetic equations in my undergrad days I stumbled upon this interesting relationship. With the very childish hopes of unifying gravitation ...
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2answers
138 views

Is it possible to calculate the force exerted by two unequal charge, separately?

According to the Coulomb's law, when two equal like point charges are placed 1m from each other the force between them is 9 * 109. But if two unequal like point charges are placed, the bigger charge ...
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3answers
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Coulomb force in SI and cgs

Coulomb force in SI is $ F = \frac{Q1*Q2}{4\pi\varepsilon R^{2}} $ while in CGS $ F = \frac{Q1*Q2}{R^{2}} $ why is it? I mean doesn't it any make difference in dimension? since $ \varepsilon $ ...
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0answers
59 views

Infinite chain of alternating charge

The problem There is an infinite chain (1d) of alternating charges that are in a distance a from each other. That is there is one charge +q and next to it -q and so on. Now calculate how much work it ...
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2answers
58 views

Could Charles-Augustin de Coulomb measure the charge in Coulombs?

Did Charles-Augustin de Coulomb know: Coulomb's constant Coulomb (as a unit) if not then what was the first time it was measured?
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2answers
91 views

How is $\text{PE} = qV$ derived using knowledge of $F = \frac{q_1q_2}{4\pi \epsilon_0 r^2}$

I recently started grade 11, and this concept confuses me, since if we place a charge $q$ on a potential $V$, I do not completely comprehend what values would need to be substituted which would give ...
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0answers
36 views

Dependence of Force as a function of Distance? [duplicate]

Why is the strength of a field (i.e. gravitational or electric) inversely correlated to the square of the radius? It is clear to me why the further you get a way from a field, the field's enacted ...
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1answer
66 views

Reduced charge for attracting electrons?

The reduced mass in the two body problem is $\mu= \cfrac{m_1 m_2}{m_1 + m_2}$. Is there any analog to this with interacting charged particles (or at least that is of use somewhere in physics)? I have ...
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7answers
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Why is there a factor of $4\pi$ in certain force equations?

I mean to ask why there is $4\pi$ present in force equations governing electricity? Though all objects in universe are not spherical and circular, the constant of proportionality in both equations ...
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1answer
58 views

Attraction and repulsion of charge? [duplicate]

Why do like charges on identical bodies cause a repulsion and unlike charges cause an attraction?
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2answers
299 views

Newton's Law of Graviation: Why $G$ and not e.g. $\dfrac{1}{4\pi G_0}$?

I've been wondering, in Coulomb's Law, $k_e = \dfrac{1}{4\pi\epsilon_0}$. Therefore, why do we use $G$ in Newton's Law of Gravitation? What if the constant is more like Coulomb's Law, e.g. $G = ...
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0answers
25 views

Electric Field: distributed uniformly in one infinity tape of length [closed]

One charge density surface is distributed uniformly in one infinity tape of length with $2a$ width from distance $d$. Determine the Electric Field in the point perpendicular from the distance $d$ ...
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1answer
29 views

Does higher voltage and plate area cause more separation between leaves in electroscope?

Does higher voltage cause more separation between leaves in electroscope? Will higher voltage and plate area attract more charge since Q = CV.
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4answers
9k views

Why do same/opposite electric charges repel/attract each other, respectively?

I know plus pushes another plus away, but why, really, do they do that? On the other hand, molecules of the same type are attracted to each other. I find that weird. I do know some stuff about four ...
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2answers
164 views

Electrostatics kinematics equations (Coulombs Law)

If there are two similarly charged particles $Q$ and $q$ of masses $M$ and $m$, a Coulomb force is applied on each one (action-reaction). Suppose that $Q$ is stationary and we are shooting $q$ with an ...
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1answer
126 views

Electrostatics-Coulomb's Law

Coulomb's Law is an experimental result $$F=k_e\frac{q_1 q_2}{d}.$$ How did or What did Coulomb do to verify this law as it is applicable for point charges at rest and in reality charges won't be at ...
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0answers
38 views

How to prove Gauss's law div(E) = rho/epsilon from Coulomb's law? [duplicate]

As we know from coulomb's law that: $$\vec{E} = \frac{q}{4\pi\epsilon R^2} \hat{R}$$ using the above equation, how can I verify that: $$\vec{\nabla}\cdot \vec{E}=\frac{q}{\epsilon}$$ I have tried to ...
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3answers
473 views

How would charge be distributed in charged conductors if the Coulomb law was not ${1}/{r^2}$?

Would the excess charge on a conductor move to surface until the electric field inside become zero if the Coulomb law was for example $\frac{1}{r^3}$? If yes, would the distribution $\sigma(x,y)$ be ...
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1answer
166 views

Maxwells' equations and Coulomb's law

Coulomb's law and Maxwell's equations should be consistant as one can be derived from the other. Say we have a point charge with such a charge that $-kq=1$, meaning that at any point the electric ...
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2answers
139 views

Relation between Gauss' law and Coulomb's law

In Coulomb's law if the relation was as if electric field intensity was to vary inversely $1/r$ with distance rather than the inverse $1/r^2$ of square of distance, would the Gauss's law still be ...
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0answers
33 views

Gauss law from Gauss divergence theorem [duplicate]

Apply Gauss divergence theorem to the gravitational field due to a spherical object of mass M and uniform density located at origin. Obtain Gauss law for gravitation in integral and differential ...
9
votes
4answers
2k views

Are the Maxwell's equations enough to derive the law of Coulomb?

Are the 8 Maxwell's equations enough to derive the formula for the electromagnetic field created by a stationary point charge, which is the same as the law of Coulomb? If I am not mistaken, due to ...
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1answer
116 views

Why Gauss' law is applied?

Why Gauss' law is applied? Why is there a need of finding electric field by Gauss' law if we can find the electric field through Coulomb's law? or has it got more applications than Coulomb's law?
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1answer
124 views

Need for acceleration in particle-antiparticle annihilation? [closed]

If an electron and positron are accelerated towards each other, at distances quite far away, there wouldn't be any significant electrostatic attraction, hence they need to be accelerated. But when ...
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2answers
103 views

Who first verified Coulomb's Law for electron+proton interaction?

Who first verified Coulomb's Law for the interaction of a proton and electron? Was it Rutherford? Bohr?
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2answers
4k views

Why exactly does current carrying two current wires attract/repel?

When to parallel wires carrying currents in same direction I1 & I2. http://www.youtube.com/watch?v=43AeuDvWc0k this video demonstrates that effect. My question is, why exactly does this happen? ...
3
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1answer
233 views

Coulomb potential

It is known that the Coulomb potential can be obtained by Fourier transform of the propagator from E&M. Is this because one of Maxwell's equations have the form $\nabla \cdot \mathbf{E}=\rho$?
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3answers
151 views

Clarity in Electric field Definition?

The electric field at a point is defined as q/$r^2$. How does this definition take the nature of source and test charge into consideration. If I bring any positive/negative charge around the source ...
15
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2answers
871 views

Is Newton's universal gravitational constant the inverse of permittivity of mass in vacuum?

Is it possible to consider Newton's universal gravitational constant, $G$, as inverse of vacuum permittivity of mass? $$\epsilon_m=\frac {1}{4\pi G}$$ if so, then vacuum permeability of mass will ...
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0answers
35 views

How to derive the classical Hartree potential for a slab system?

I am now working on a slab system, but encountered some problems on the classical Hartree potential. This slab system is infinity along x-y plane, and has finite size along $z$ axis $z\in[0,L]$. I ...