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

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Definition of Static Electricity

The result of an imbalance of electrons between objects is called static electricity. It is called "static" because the displaced electrons tend to remain stationary after being moved from one ...
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Finding the Steady State Charges

Here the problem states to find the steady state charges on the condensers.<<<< According to me the charges on second at steady must be ...
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308 views

Infinite Energy of Point Charges (in the context of classical field theories)

In the context of classical physics,is there any renormalization method to avoid infinite energy of point charges?
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408 views

Why do aqueous solutions always “have to be” electrically neutral?

I was reviewing some analytical chemistry and stumbled upon a section that explained the imperfection of using a salt bridge. It said that the using dissimilar ions is a problem because in, for ...
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234 views

About the electrostatic voltage

What's the difference between electrostatic voltage and normal voltage, like the battery's voltage. How to calculate the charge on a charged plate if we knew its electrostatic voltage?
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369 views

Induced charge on sphere

I have a conducting sphere ($radius = a$) at potential $V_0$. It is enclosed by another thin shell ($radius = b, b > a$) which has a charge density $\sigma (\theta) = \sigma_0 \cos(\theta)$ for the ...
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264 views

Regarding the free electrons on the conductor

In a metal, why don’t the free electrons fall to the bottom of the metal due to gravity? Also, charges in a conductor are supposed to reside on the surface so why don’t the free electrons all go to ...
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86 views

Static electrical attraction [closed]

Coulomb's law is used to calculate the electrical attraction between 2 charged particles, what formula do I use to calculate an electrical attraction magnitude between 2 plates? Let's assume the first ...
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304 views

Do objects have energy because of their charge?

My gut feeling tells me things should have energy because of their charge, like they have energy because of their mass. Is this possible? Has it been shown? If not then what is missing to make such ...
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If photons can be absorbed by electrons, wouldn't that mean light has a charge? [duplicate]

I am a biochemistry and molecular biology major. If photons can be absorbed by electrons, wouldn't that mean light has a charge? Electrons only attract positive charges. Isn't it?
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How can I prevent my son building up static on his trampoline?

Whenever my three year old son plays on his trampoline, it doesn't take very long for him to start building up a significant amount of static electricity. His hair stands on end (which is quite ...
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Why is the charge transferred by electrons and not by protons?

charges are transferred by electrons which we all know but why it cant but it cant be transferred by protons.Well i searched on google where i found similar questions already being asked on many ...
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219 views

Make water droplets charged?

Normally water molecules are electrically neutral. But I have seen somewhere ideas about electric energy generators mentioning that water droplets might be used in some applications as they are ...
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How quark electric charge directly have been measured?

How quarks electric charge directly have been measured when quarks never directly observed in isolation? (Due to a phenomenon known as color confinement.)
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Facts About Quarks Electric Charge [duplicate]

Quarks have the unusual characteristic of having a fractional electric charge. here there is a new model that suggests maybe an up Quark has no electric charge and infact down Quark has electric ...
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How can I find the position of an image charge when the boundary is parabolic or hyperbolic?

If the position of some charge Q is known, the boundary condition is u=0 on some parabolic surface, and we know the image charge has its electric volume of Q', then how can I determine the position of ...
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1answer
236 views

Find the dielectric constant of the medium?

Two point charges a distance $d$ apart in free space exert a force of $1.4\times10^{-4}N$. When the free space is replaced by a homogeneous dielectric medium, the force becomes $0.9\times10^{-4}N$. ...
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162 views

Total positive charge in the Universe

In their last homework, some of my students miscalculated a charge to be $10^{20}$ C over a squared meter and I was wondering if there was as much positive charges in the entire Universe. It would do ...
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175 views

Is electron velocity at induction higher than in a wire?

When looking to the electrostatic induction on a microscopic level, do the electrons really move with high velocities or they move like when a current passes through the wire (slowly).
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572 views

Does the electric field inside a sphere change if point charge isn't in center?

As i understood , if you have a point charge in the center of a hollow conducting sphere then the electric field inside it, is zero because the charge distribution is spherically symmetric. But ...
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469 views

Parallel capacitors without battery. Does charge flowing after a dielectric input?

If I charge two capacitors which are connected parallel $[$the minus (-) of the one opposite to the minus (-) of the other and the plus(+) of the one opposite to the plus (+) of the other.$]$, will I ...
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482 views

Two capacitors sharing charge

My two capacitors:                               I have these two capacitors ($C_1 = 3\mu F, C_2 = 4\mu F$) both initially under 19 volts. Then, I added a dielectric with $k=4$ at $C_1$ and entire ...
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523 views

What's the electric field with a point charge not in the center of the sphere? [closed]

That's a hollow conducting sphere link My charge is at P (10uC). R = 0.15m. PS = 0.05m. DS = 0.35m. What's the electric field at point D?
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47 views

Charge residing on an overpolished surface

I had very well read that when charge is stored on a rough surface, the leakage is very high from the pointed tips of such surfaces, by a phenomenon called action of points. But now, I've come to know ...
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Why doesn't a gaussian surface pass through discrete charges?

I have read that Gaussian surface cannot pass through discrete charges. Why is it so? I have even seen in application of Gauss' Law when we imagine a Gaussian Surface passing through a charge ...
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Electrostatic induction

Is this a correct definition of electrostatic induction, The production of opposite charges on a neutral body when a charged body is brought near to it? I think it's not the production but ...
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353 views

Electric field of a negative charge

Displacing something against the gravitational field, gains it potential energy. Moving something against the nature requires work. If the electric field of a negative source charge 'Q' points inward, ...
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Electric field of a negative charge

How was it discovered that the electric field of a negative charge points towards the charge itself? Is it true? (Courtesy of wikipedia)
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Origin of electric charge

Baryons have charges that are the result of a polynomial calculation of their building blocks (quarks)'s fractional charges. But what gives these quarks electric charges? What interactions do they ...
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235 views

Point charge 4-current derivation

How do I derive that the 4-current of a point charge is $$j^{\mu}(x)=ec\int_{-\infty}^{+\infty}\dot{z}^{\mu}(s)\delta(x-z(s))ds$$ where $\dot{z}^{\mu}(s)$ is the 4-velocity of the charge and $s$ is ...
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Electrostatic potential and charge

Say we have a balloon, negatively charged, the voltage on it is 500 V. Can I measure the charge on it or in other words, the number of excess electrons?
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76 views

Electric charge and the distance

The strength of an electric field is: $E = 200\ \mathrm{N/C}$ The potential (of the test charge) is: $V = 600\ \mathrm{V}$ $\epsilon_r=1$ I need to calculate the distance between this point and the ...
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How to positively charge an object with a power source? [duplicate]

How do you positively charge something consistently? By what mechanism could this be achieved?
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2k views

Electron volt and Voltage

Voltage is the work done per unit charge. Given by: V = W/q Electron volt is the maximum kinetic energy gained by the electron in falling through a potential difference of 1 volt. Given by: K.E ...
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What do physical properties of materials trigger the capacitive touch screen?

I have watched some youtube videos about capacitive touch screen http://www.youtube.com/watch?v=ZHzaVzYEZbw http://www.youtube.com/watch?v=GmCE18RMEeQ The videos show that a conductor(finger), in ...
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Empirical bound on sum of electron and proton charge

Followup to "Why do electron and proton have the same but opposite electric charge?". It is argued that even a tiny residual charge would result in huge amounts of electricity in bulk matter, ...
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Explanation on the resulting forces of two positive point charges

Why will the resulting force lines of two positive point charges be like this: I would expect this:
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How does positive charge spread out in conductors?

I know that when there are excess positive charges in a conductor, for example, a metal sphere, the positive charges will spread out over its surface. However, I am confused about how this excess ...
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If a particle is a point of high intensity in a quantum field, how can it have charge?

The charge of a fundamental particle is a mysterious but obvious and well-known property of every non-neutral particle. I can understand how, if a particle is an object, or thing, for want of a ...
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How is possible for current to flow so fast when charge flows so slow?

How is possible for current to flow so fast when charge flows so slow? We know electrons travel very slowly while charge travels at ~the speed of light.
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Why can we use Gauss' law to compute electric field?

For simplicity I'm considering only the sphere case. In the Gauss' Law formulation we have some field $E$ introduced by charges $Q$ inside some sphere, then we compute flux and integrate, and we get ...
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What happens to capacitor’s charge when the plates are moved further apart?

In my physics textbook there is an example of using capacitor switches in computer keyboard: Pressing the key pushes two capacitor plates closer together, increasing their capacitance. A larger ...
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79 views

Permanently charging a sphere by induction using a high voltage

I want to charge a sphere using a van de graff generator , it would sound easy , but using a 1 MV or a 900 KV is really hard, it is enough to break like 1 meter of air so whenever i try to ground the ...
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Was the fractional model of quarks electric charge found before discovery of the $\Delta^{++}$?

From Wikipedia: Existence of the $\Delta^{++}$ , with its unusual +2 electric charge, was a crucial clue in the development of the quark model. the fractional model of Quarks electric charge was ...
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Ashcroft Mermin Eq. 17.47ff

In "Solid State Physics" by said authors, Eq. 17.46 is $$ \rho^{ind}(\textbf{r}) = - e[n_0(\mu + e\phi(\textbf{r})) - n_0(\mu)]$$ and then the authors write In the present case we assume that ...
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141 views

Charged plane in an electric field acceleration

A perpendicular plane to an electric field's lines of force has more electric flux than a plane that is in parallel with the lines of force, right? Does this mean that a charged plate would ...
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189 views

Electrostatic charge leakage

What are the ways electrostatic charged objects leak charge in humid conditions? Can airborne particles pick up charge by contact, then be repelled hence removing charge? If so would it be a ...
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424 views

Electric Fields

The problem I am working on is, "In the figure below, determine the point (other than infinity) at which the electric field is zero. (Let $q_1 = -2.45\ \mu C$ and $q_2 = 6.5\ \mu C$) Here is a little ...
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545 views

Electric Field due to a charged sphere

Suppose we have a spherical surface with a surface charge density varying as $cos(\theta)$. Apparently one can find the electric field both outside and inside such a spherical surface by superposing ...
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290 views

Conservation of Energy as Applied to Point Charges

The following question appears to be extremely straight forward, but I can't seem to be able to obtain the correct answer. The question is: A charge Q1 = 1.3uC is at rest and is located 2.3 cm ...