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

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21 views

Does a capacitor experience a Newtonian reaction when being charged?

Say I have a capacitor that is being charged with a battery. There are two wires, one on the positive and one on negative terminal of the battery which go to a capacitor. During the charging, a ...
2
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2answers
42 views

How can “…electrons flow in metals, but not in the ground…” explain grounding rods?

I really enjoyed Why is the charge naming convention wrong? But, in the comments at the very end, the statement that "...electrons flow in metals, but not in the ground..." left me uneasy. I was ...
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2answers
44 views

Understanding parallel plate capacitors [on hold]

I need help with understanding this assignment. I originally though of using the equation of Eo*A/D = Q/ΔV but I don't know how to answer this without actual numbers to plug in besides the epsilon-not ...
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14 views

Linear Charge distribution in thin (conduction) beam due to electric field

I'm trying to figure out the linear charge density in a very, very thin conductive beam of 0 net charge due to an electric field generated by a source very, very far away. Since the beam is ...
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43 views

Is there anything that has mass but no charge?

Is there anything that has mass but no charge? I am of course aware of neutrons, but since these have internal structure and only a net non-zero charge, they will have a non-trivial electric field ...
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1answer
60 views

Mass of a point charge [closed]

A point charge is defined as an electric charge at a mathematical point with no dimensions(Wikipedia: https://en.wikipedia.org/wiki/Point_particle#Point_charge). Can anything be said about its mass in ...
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2answers
61 views

Finding out the charge density (electrostatics) [closed]

A solution to the potential in the region $ -a < y <a$ , where there is charge density $\rho$ , satisfies the boundary conditions , $\phi = 0$ in the planes $ y = -a$ and $y = a$. $$ \phi = ...
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22 views

Symmetry arguments and plane sheet of charge [duplicate]

The electric field due to a infinite plane sheet of charge is given by $\sigma/\epsilon_o$. Now could we have deduced by symmetry that the electric field's magnitude won't depend on distance?
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1answer
31 views

Electrostatics: Cylinder and conducting plane question (method of images)

I was looking at some problems/questions about electrostatics and came across this question: An infinitely long cylinder of radius $a$ and with charge density per unit length $\lambda$ is placed ...
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2answers
52 views

Some confusions regarding electrostatic shielding

A spherical conductor A contains two spherical cavities as shown. The total charge on conductor itself is zero. However, there is a point charge q1 at the centre of one cavity and q2 at the centre ...
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1answer
32 views

Why are there no charges inside a conducting sphere?

Why is it necessarily true that all charges occupy themselves only on the surface of a conducting sphere, and not anywhere inside the sphere? One argument is that if a charge were to be inside a ...
1
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1answer
33 views

Definition of Charge [duplicate]

Please give me a definition of charge. A textbook I have defines it to be - "A fundamental property of matter, which determines whether the matter will receive an electric flow or liberate one" I ...
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2answers
34 views

Electric charge difference weapon? [closed]

We all know how lightning works: The clouds have a strong static charge and release that charge towards the ground. But could it be used as a weapon? Would a weapon of the following description work? ...
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0answers
44 views

Where to place a charge to establish net force of 0? [closed]

A charge, Q2 = -15.00x10^-6 C, is 10.00 cm to the right of charge Q1 = 18.00x10^-6 C. Where can a third charge be placed, along the line connecting Q1 and Q2, such that it experiences no net force ...
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0answers
14 views

(boundary conditions) Interface between two lossless media

I'm wondering why there's usually no free charges nor free currents in the interface between two lossless media? no free current "I guess" is due to the insulating nature of a lossless media but why ...
3
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0answers
54 views

Why doesn't an electron's charge rip the electron apart?

Like charges repel. What keeps an electron's charge from repelling itself? This problem would come up if an electron was divisible and its parts had fractional charge. A related question is, what ...
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2answers
54 views

Why is the mass of neutrino expressed in electronvolts?

The definition of electronvolt (eV) from wiki is In physics, the electronvolt (symbol eV; also written electron volt) is a unit of energy equal to approximately 160 zeptojoules (symbol zJ) or ...
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1answer
31 views

Does the electromagnetic force “split” at lower than normal energies?

Since we have working models for forces "combining" or being describable via a single framework at higher energies (such as the "electroweak" force and the aim of GUTs), does electromagnetism split ...
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1answer
53 views

if there is no electric field then any charge exists or not? [closed]

If we assume a region of space in which there is no electric field, can we say that no electric charge exists? I think that there is no electric charge particles to create electric field for this ...
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1answer
66 views

Protons, electrons and integers

From this calculation (https://uk.answers.yahoo.com/question/index?qid=20080724101956AA4zed1), two protons seperated by the distance of one atom feel the electromagnetic force repelling them ...
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2answers
61 views

Kaluza Klein charge

If I take a $(d+1)$ dimensional Einstein Hilbert Lagrangian $L_{d+1}=\sqrt{-\hat{g}} \hat{R}$ and perform a standard Kaluza Klein dimensional reduction by periodically identifying one direction, let's ...
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2answers
54 views

Are charges absolute or relative?

The charge of a particle is (mostly) an intrinsic property of the particle. One of the few elementary particles that doesn't have a charge are neutrino's. Does that mean that it is still possible ...
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1answer
63 views

How did scientists manage to measure the charge of electron so precisely?

According to the latest CODATA reports the charge of electron is known very precisely $\approx 1.6021765314 \times 10^{-19}$. My question is: How is this charge determined with such high precision? ...
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1answer
24 views

Can polarization occur if both charges are neutral?

If I keep neutral conductive pieces of some metal close to a neutral conductive sheet, what will happen? Will any of them get polarized or nothing will happen. My guess is nothing will happen as for ...
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2answers
30 views

Why does current density changes but not current? [closed]

let us assume that we have a conductor with a specified resistance ( case 1 ) and a normal conductor ( case 2 ) as shown in the figure , and now we apply an external electric field with a battery on ...
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33 views

Charge on Earth [closed]

We know that the Earth is neutral. But what will happen if the Earth becomes negatively charged or positively charged somehow?
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32 views

Why is spacetime curved by mass but not charge [duplicate]

According to general relativity theory, the deformation of spacetime is proportional to energy tensor $$T_{\mu\nu}.$$ $$ R_{\mu\nu}-\frac{1}{2}g_{\mu\nu}R = 8\pi G T_{\mu\nu}. $$ Does it mean that ...
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1answer
50 views

Will charges attract or repel?

If the universe consist of only two particles namely electron and proton, and if they are separated away by huge distance, they will still attract each other. Can we prove it without using Coulomb's ...
0
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1answer
22 views

Force from a large conducting plate [closed]

How can I find the distance to a test-charge, hoovering below a conducting plate? Newtons laws applies. $$ $$ According to this information, I conclude that the force is equal zero. It is not ...
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1answer
22 views

Electron gun; potentials around charged plates

I know that an electron gun releases electrons by thermionic emission and accelerate the electron through charged plates, and that the electrons are not gaining any energy after they leave the gap ...
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1answer
29 views

What is the difference between charged body and conductors?

In charged bodies,charges can be uniformly distributed all over it's volume, but in conductors charges always lies on it's surface. Please tell me the difference between charged bodies and ...
3
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0answers
35 views

How exactly are the relative strengths of gravity and electromagnetism quantified? [duplicate]

I've often heard it said that gravity is much weaker than electromagnetism, and after looking at several questions on SE, I feel that I've got at least a qualitative handle on the concept -- gravity ...
1
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1answer
38 views

Why is it true that Laplace's equation does not hold within the sphere in this case?

Find the average potential over a spherical surface of radius $R$ due to a point charge $q$ located inside. (In this case Laplace's equation does not hold within the sphere) This is a question ...
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20 views

Is the electric field inside a conductor always zero? [duplicate]

We just learned in physics that a field inside a conductor is zero. My question is, is this always true? For example, what about if you were inside a hollow iron sphere 10 feet from a hugely ...
3
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1answer
57 views

Charge distribution in electron

In the Wikipedia article Classical electron radius in calculation of radius of electron. Charge distribution of electron described as $$\rho(r)= \frac{q}{4{\pi}Rr^2}$$for $r\leq R$. This is variable ...
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51 views

Gauss's law giving incorrect answer

Let's consider two concentric spherical shells, one of radius $R$ and one of radius $R - \Delta R$. The outer shell is negatively charged and the inner shell positively, but both the shells have net ...
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1answer
81 views

Distribution of surface charges in an electric circuit

I'm reading Sherwood and Chabay's brilliant textbook Matter and Interactions, in particular the section that deals with how the surface charges in an electric circuit distribute themselves to generate ...
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3answers
89 views

If we consider the electric field to act upon charges with a force, how does it stay in line with Newton's laws?

This should be a relatively simple question. Let's say we have a constant electric field $\textbf{E}$ in a conductor. The electric current density would then be $$\textbf{j}=\rho \textbf{v}$$ where ...
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1answer
98 views

Enhancing the QED $U(1)$ gauge symmetry

QED is a gauge theory based on $U(1)$ gauge symmetry, which gives rise to photon as the gauge boson mediating the interaction. Mathematically, I think it is perfectly allowed to implement a ...
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30 views

Circuit with three capacitors

A potential difference of V = 38.0 V is applied across a circuit with capacitances C1 = 4.1 nF, C2 = 4.7 nF, and C3= 2.3 nF, as shown in the figure. What is the magnitude and sign of q3l, the ...
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44 views

What is the relation between charge and polarization?

On one hand, in this "Measurement of polarisation" lab manual, polarization is surface charge density, $P=\frac{Q}{A}$, in other words, charge an polarization are essentially the same thing. On the ...
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10 views

Measure a current from a charged surface caused by charge separation

I have separated a charge in an electric field like here (http://elektroniktutor.oszkim.de/grundlagen/gr_pict/coulomb5.gif) and I put the metal out of the field. The charge density on the surface of ...
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18 views

Point charge inside a electrically neutral cavity in conductor placed eccentrically, and effect of external electric field if switched on

bear with me, but i would like a definite answer, now, starting off the external charge density on the outer surface of sphere WILL be uniform by unique solution of Laplace equation and letting the ...
0
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1answer
81 views

Why doesn't gravity have charges?

All other forces have some kind of charge system, electromagnetism has positive and negative, weak force has hypercharges, and strong force has colors. Why doesn't gravity have anything like these?
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84 views

How does a charge distribution evolve with time? (in classical electrodynamics)

It is often stated that, in classical electrodynamics, the electric and magnetic fields determine uni vocally the dynamics of a charge distribution distribution (how it evolves in time). I can more or ...
1
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1answer
59 views

Coulomb's Law and conversion of nano-columbs/coulombs

This is not a homework problem. I am working ahead for my Electricity and Magnetism course for next quarter and this is a Chapter 25 video tutor solution question pearson put out where they do a short ...
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2answers
34 views

Distribution of Electric Charge on the surface of Sphere - simple explanation? [duplicate]

Which basic physics principle could I use to formulate a simple explanation of the homogeneous distribution of electric charge on the surface of a hollow metallic sphere? P.S.: targeted audience with ...
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24 views

Extreme charge density in thin capacitor plates

Suppose we made a 1 square meter parallel plate capacitor from two sheets of graphene separated by a very strong dielectric of arbitrary thickness. Then we charge the capacitor just short of the ...
2
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2answers
53 views

Are charges always uniformly distributed on conductors?

As the title says. For example, if I take a fat metal wire with non-negligible thickness, and then wind it into a spiral, but such that none of the parts touch one another (there are no topological ...
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82 views

Problem related to application of Maxwell's equation for point charge moving uniformly

Maxwell's 4th equation which describes magnetic field, has two terms: $$ \oint \mathbf{B}\cdot d\mathbf{l}=\mu I+\mu \varepsilon \frac{\mathrm{d}\Phi}{\mathrm{d}t}$$ Now, I wanted to derive the ...