A fundamental property of matter which causes it to experience electromagnetic forces.

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What is the definition of electrical charge? [duplicate]

In one simple sentence what is the definition of charge as I don't understand what role it has in a circuit. Thank you
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1answer
54 views

What is maximum energy we can extract from electric field?

I was reading Does Electric field has mass Energy; it gives energy density k stored around an electric charge as $ k = \dfrac{q^2}{r^4}$ in skeleton form without any constants. So, a definite amount ...
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1answer
33 views

Motion of an electric charge within an electric field with two electric charges

Assume that air resistance and gravity are negligible and the only significant force acting in the scenario is the electric force. There are two electric charges, both with an equal and positive ...
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3answers
66 views

Spherical Shell with Electric Field Zero Everywhere Inside It

If an isolated, charged spherical shell has a uniform charge distribution, the electric field everywhere inside it is 0, by Gauss' Law. Is the converse true? That is, given an isolated, charged ...
2
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2answers
58 views

Do Weyl fermions carry electric charge?

Do Weyl fermions carry ordinary electric charge? That is, do they interact with, for instance, electrons or photons?
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1answer
52 views

Surface density charge, divergence of the electric field and gauss law

It´s known that the divergence of the electric field at a certain point is given by this formula: $$\nabla \cdot E=\dfrac{\rho (r)}{\epsilon_{0}}$$ Being $\rho (r)$ the volume charge density at that ...
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1answer
53 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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0answers
32 views

What exactly is Breakdown Voltage of Air?

Most of the online sources say that the breakdown voltage of air is 30kV/cm. I've made a Cockcroft Walton multiplier and I can see the air breaking in between 17-18kV/cm. Only in a discussion at one ...
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0answers
67 views

Why is there no negative mass? [duplicate]

We know that the entire matter has a property called mass. Charge is also a property of matter. If negative charge can exist, why don't negative mass exist? Also, like charges repel each other. Then ...
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1answer
41 views

What are all charge-like quantum numbers?

What are all charge-like quantum numbers? In particle physics there are often things (like charge conjugation) that apply to all charge like quantum numbers. Everytime I read something about charge-...
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0answers
14 views

Potential energy of a shell & point system

Consider the system of a point particle with charge $q$ and a spherical shell with uniform charge $Q$ and radius $R$ whose center is a distance $r > R$ away from the point particle. I'm trying to ...
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9 views

Charge distribution parametres

I'm reading an article regarding charge distribution parametres in muonic atoms ad I'm stuck in the very first pages. In particular, I don't understand, given a 2-parametre Fermi charge distribution ...
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1answer
43 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
55 views

Gauss's law, electrical flux density [closed]

Q. Given a 60-μC point charge located at origin, find the total electrical flux passing through the plane z = 26 cm. I can understand what the question means, but I can't do anything. Is it using ...
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0answers
22 views

Choosing between a parallel-plate and spherical capacitor model

This problem is solved in the solutions manual by making reference to equations for the parallel-plate capacitor. I have some basic understanding of why this is the case (the local curvature is small ...
2
votes
1answer
135 views

What is the difference between emu and esu?

Ok...so this is the statement given in my book: a) In C.G.S System the unit of charge is electrostatic unit of charge (E.S.U). It is also called Stat Coulomb (StatC). b) In C.G.S system, the unit ...
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2answers
17 views

Electric potential energy of a charge

Potential energy is the work done by the particle against a conservative force. Isn't it? when a charge is fixed on a free space and then when we bring another charge from infinity to a distance r ...
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0answers
44 views

Charged conducting wire ring and Greens function

ρ(r) = q 2πa2 δ(r − a)δ(cos θ). If this is my charge distribution on a conducting wire ring. radius=a. I am attempting to show my electrostatic potential as an integral along the z-axis I started by ...
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0answers
24 views

Why do they rub rubber with wool while glass with silk and not otherwise?

why not the other way round, and why do they choose wool and silk in particular to charge the rubber and glass rods ?
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3answers
71 views

Why does adding more components in parallel increase the current?

Why does adding more components in parallel increase the current? Shouldn't the charges be more distributed, so they can't 'push' each other at the same rate anymore?
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0answers
42 views

Method of image charges — Why is a *grounded* plate needed?

In the classic image charge problem of a charge $q$ above an infinite grounded plane, it is well known that the field lines essentially behave as though there were a negative charge behind it, and the ...
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3answers
89 views

Why charge is not a measure of inertia?

We know that mass is the measure of inertia of rest. Then why charge is not a measure of inertia? What causes the difference between charge and mass?
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0answers
39 views

What's the relation between representation theory and mass / electric charge?

This is a follow-up on this answer, where ACuriousMind wrote Formally, both the mass and the charge classify certain irreducible representations of the Poincaré group and the circle group, ...
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0answers
39 views

Force on a charge due to charged sheet

I want to find the force on a positive charge placed at a distance $d$ from a positively charged infinite plate. Of course, it can simply be done by finding the electric field due the plate using ...
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1answer
50 views

The charges of the forces

I am trying to establish a simplified understanding of the fundamental forces to explain them to a young audience. If we say that gravity has one charge (attractive), electromagnetism has two charges ...
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1answer
51 views

Are objects generally neutral or charged?

Basically the questions relates to what is taught about electroneutrality and has 2 parts: Is the overall charge in the universe zero? Are objects the world generally neutral or slightly charged, ...
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1answer
61 views

Electric flux of a charged rod through a uniform disc

I have an assignment regarding electric flux. The question I was given has the following sketch: The first question was about the force on the rod from the disc at the $z$-axis. I reached the ...
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2answers
84 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 terminal....
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0answers
34 views

Electrostatic potential due to angular dependent spherical charge distribution

Problem: Given the charge density $\rho = \rho_0 \frac{r}{a}\sin{\theta} \sin{\phi}$ for $r<a$, and $0$ for $r>a$, calculate the electrostatic potential. Issue: I have previously done a ...
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1answer
20 views

How to discharge a plastic surface? [closed]

In a plastic sheet surface, how to make the surface charge disappeared ?
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3answers
58 views

Charge moved across a potential difference; where does the energy for emitted radiation come from?

Let's use an electron and a 1V potential difference as a mode. In school I learned that if the electron is at the negative end of the electric field, its potential energy is equal to the work that ...
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1answer
77 views

Magnetic Field in parallel plate capacitor [closed]

A parallel plate capacitor of area 60cm^2 and separation 3mm is charged initially at 90 micro coulomb. If the medium between the plates get slightly conducting and the plate loses charge initially at ...
0
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1answer
39 views

Applicability of coulombs law for objects in different dielectric media

Is the Coulombs law applicable for inter-medium interaction? Consider the example image shown below How can one deduce the angles the bobs might make if they are in different dielectric medium?...
3
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2answers
99 views

Has such experiment been performed before?

Consider a charge of 1C kept a distance of $6*10^8$ m from a detector. I find electric field due to this charge at detector. Then, I suddenly earth that charge and not the time it takes to be ...
2
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3answers
98 views

What is a charge? [duplicate]

If mass is the measure of the inertia of a body, then what is a charge? Everyone tells that it is a fundamental property but i believe it must have a unique definition. Anyone know in this regard?
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2answers
72 views

Electric field due to a charged irregularly shaped balloon

There is a question in my textbook that says: A rubber balloon is given a charge $Q$ distributed uniformly over its surface. Is the field inside the balloon zero everywhere if the balloon does not ...
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0answers
27 views

Alpha Radiation - Charges [duplicate]

Has the radiating material that emits only alpha radiation a negative charge? I am just wondering, because alpha radiation is a positive charged helium ion - so where are the electrons going?
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5answers
106 views

How is the electromagnetic field made?

I know that an electric field is created by a particle with a charge and that a magnetic field is created by a moving charge but how do they combine to make a electromagnetic field?
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1answer
124 views

Why do fundamental particles have charge? [duplicate]

More specifically, what is in the nature of these particles that they carry a charge, and thus repel objects of similar charge and attract those of opposite charge? Also, why would the charge of an ...
1
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0answers
71 views

The charge density of the electron cloud of a hydrogen atom has a total charge different than an electron's charge [closed]

The charge density of the electron cloud for a hydrogen atom in the ground state is according to quantum mechanics:$$\rho(r)=\dfrac{q}{\pi a^3}e^{-2r/a}\tag{1}$$ where $a=a_0$ is Bohr's radius and $q$ ...
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1answer
246 views

Is there a charge density in quantum mechanics?

Is it meaningful in quantum mechanics to speak of charge distribution? Some people say if you sovle the Schroedinger Equation for the hydrogen atom, the eigenfunctions represent a type of charge ...
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0answers
58 views

Derivation of exponential charge distribution and form factor from the normalized yukawa charge distribution and form factor

For a problem solving class I need to derive the normalized exponential charge distribution $\rho_e \propto e^{-\mu r}$ and corresponding form factor $F_e$, from the normalized Yukawa distribution $\...
0
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1answer
40 views

How does a capacitor get charged while the charger circuit isn't closed? [closed]

a capacitor is a very known device in circuits that can be used as a short-time battery by charging it using another source, but how does it really get charged? if the plates of the capacitor don't ...
0
votes
2answers
69 views

What does the movement of charge in an object mean?

When it is said that charge "moves" throughout an object, like if negative charge moves to the edge of an object and the charges become polarized, does this mean that the electrons has moved to the ...
0
votes
1answer
87 views

What does the 'charge' of the electron transform into when the electron gets converted to wave? [closed]

Mathematically when a particle exhibits wave nature, its mass is supposed to be converted into energy. I want to know what happens to the charge of particle? what does the 'charge' of a non ...
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votes
3answers
49 views

Why is it that when potential difference across a capacitor is equal to the supply voltage, no flow occurs?

Can someone explain to me how and why this happens? I'm really confused. I'm also confused about how the net charge between 2 plates is 0.
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1answer
26 views

Negative ampere and graphical convention

Since only electron's flow in electricity and electrons have negative charge, then why we don't say —1amps (—1C/s)? Secondly, as conventional way we write down independent variable in $x$ axis and ...
5
votes
4answers
122 views

What carries electric field through space?

A stationary charge "creates" a constant (but not uniform) electric field around it, and a moving charge "creates" a variable electric field around it. What "carries" the information about the ...
0
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0answers
44 views

What causes certain particles to have charge? [duplicate]

The three major measurements for the elementary particles are mass, spin and charge, mass is supposedly achieved through interaction within the Higgs field due to the Higgs effect, spin is the angular ...
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2answers
130 views

How much is a Coulomb, really?

I've heard it said in my physics class that a Coulomb "is a lot of charge". And I believe it; most of the problems I've done in the class so far involve charges on the order of micro-Coulombs (or, ...