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

learn more… | top users | synonyms

1
vote
2answers
38 views

Draw the charge configuration according to the electric field [on hold]

I'm trying to draw the charge configuration outside the regions that lead to the given electric field patterns. Can someone show me how?
0
votes
1answer
31 views

Gauss's Law :Electric field due to uniformly charged sphere

While determining the electric field due to a uniformly charged conducting or non-conducting sphere,does the sphere is considered hollow or it is considered solid? Can anyone really state , what is ...
0
votes
0answers
7 views

Would the charges on a superconductor near an another charged conductor move and produce magnetic field?

When there is a charged conducting object near an another charged conducting object the charges on these objects accumulate to the sides where the closest points between these objects are. However, ...
2
votes
1answer
42 views

Electric charge of light? [duplicate]

Light (or any radiation as a matter of fact) is an electromagnetic wave so why doesn't it have a electric charge associated with it? As far as I know only static or flowing electric chargers can ...
0
votes
2answers
38 views

What is the difference between electric charge and electric flux?

What is the difference between electric charge and electric flux? According to my knowledge electric flux is nothing but electric charge enclosed by the closed surface.
6
votes
3answers
305 views

Why are there no elementary charged, spin-zero particles?

In the spirit of a related inquiry, I would like to know if there's a basis for understanding why there aren't any elementary particles that have non-zero electric charge but zero spin? Can such a ...
0
votes
0answers
36 views

Charge distribution over a finite plate

Let's say we have a tube(simply a cylinder with no top or bottom) with charge $q_1$, radius $r_1$ and length $l_1$ made out of insulating material. There is also a finite conducting plate with sides' ...
2
votes
1answer
286 views

Why isn't the quark charge taken as primitive?

Why are electrons taken implicitly to be the elementary charge? It would save a lot of fractions in particle physics problems.
1
vote
1answer
61 views

How would the universe change?

How would the universe be modified if protons (as we know them) have negative charge and electrons (as de know them) have positive charge.
1
vote
1answer
33 views

Is the charge of an ion evenly distributed?

This question relates to: Gauss' law and ions? Is the charge distribution in an ion spherically symmetric due to quantum mechanical effects or do we assume it when using Gauss's law, as in the ...
0
votes
1answer
23 views

Gauss' law and ions?

My text book says that with we have a singly ionized sodium atom net charge +e and if we choose a spherical surface centered on the ion and large enough to contain it all we do not need to know the ...
2
votes
1answer
75 views

Charge vs Charge Density in classical electrodynamics

What is assumed to be a more fundamental physical quantity in classical electrodynamics. The charge density as a scalar field or the physical entity charge.
4
votes
1answer
119 views

Electron Charge is 150%?

Is there a theory for why the charge of an electron is precisely 50% larger (magnitude) than a quark's? I have usually thought of this the other way around: the charge of a quark being 2/3 (or -2/3) ...
0
votes
2answers
74 views

How can I split a resultant force into its $x$ and $y$ components?

Point charge 3.5μC is located at x = 0, y = 0.30 m, point charge -3.5μC is located at x = 0 y = -0.30 m. What are (a)the magnitude and (b)direction of the total electric force that these charges ...
0
votes
1answer
28 views

When two spheres of equal charge make contact, why does the larger sphere gain more charge?

Suppose that two spheres, $S1$ and $S2$, with radii $R1$ and $R2$ resp. have the same charge uniform charge $Q$ and $R1 > R2$. After they are forced to come in contact, why does $S1$ gain more ...
2
votes
2answers
25 views

Unequally charged hanging pith balls

I have done a problem which asks us to find the charge on two equally 'massed and charged' pith balls which are left hanging on a string with a certain length that repels each other and attains an ...
0
votes
1answer
41 views

How to distribute static charges evenly on a finite plate?

There are several ways to make charges on an object evenly distributed. For example, if the surface of the object is infinite or the object is a sphere. There is one more way which I am not sure if it ...
1
vote
3answers
51 views

How can metal objects become electrically charged, if current flow means that an equal number of electrons enter/leave the object?

I am trying to answer to the question in the title. I am restricting my question to metal objects only. Here is my logical reasoning: Current is the flow of charge over time. In a circuit (simple ...
3
votes
1answer
102 views

Understanding the Charge Conjugation Operator

I am trying to understand the charge conjugation operator. http://en.wikipedia.org/wiki/C_parity Because the operator is Hermitian, this seems to imply that there is a (possibly spontaneous?) ...
2
votes
2answers
33 views

Do charges flow from strong insulator to weak insulator?

Do static charge in a strong insulator flow to a weaker insulator when both stay in contact with each other? For example, when an insulator weaker than air placed in a medium of air, would the static ...
1
vote
1answer
35 views

How to find whether the electric field between capacitor plates is above or below the electrical breakdown limit of the insulator between the plates?

Let's say the two plates of a capacitor have charges $q_1$ and $q_2$. The separation between these plates is $d$. I know that I can calculate the electric field by dividing the voltage that is applied ...
2
votes
2answers
55 views

How much voltage should be applied to an object to create a certain amount of charge?

I am curious as to how much voltage should be applied to create a specific charge. Is there a formula to calculate it, and what are the parameters that can affect the relation between voltage and ...
2
votes
1answer
41 views

What is the best insulator for static charges? [closed]

I am trying to find a solid material that almost fully (since there is not a thing that can fully insulate electricity) blocks static charges from one layer to another. I know plastic is a good ...
0
votes
0answers
32 views

How to calculate electric force between two tubes?

Let's say the electric field due to a charged tube is $E$,length of the charged tube is $l$, radius is $r$ and the surface charge density is $\lambda$. I know that to calculate the electric force ...
0
votes
1answer
17 views

Can non-conductive materials can be grounded by a wire?

Suppose that I comb my hair. The plastic comb would become negatively charged and would attract small paper pieces. But if I touch the comb in bare hand and in bare foot standing on the ground, or if ...
0
votes
1answer
24 views

Conducting sphere with a cavity

I have a conducting sphere which has a cavity in it. The cavity is not at the center of the sphere. If a charge $+q$ is placed inside the cavity (with the sphere remaining neutral as a whole), what ...
2
votes
1answer
57 views

Magnetic moment of uncharged particles

As we know that particles, only having charge, can have magnetic moment, then how particle like neutrino (having mass) can have magnetic moment? Don't bother about neutron because it has charge ...
0
votes
0answers
29 views

What do we mean by electromagnetic charge? [duplicate]

What do you mean by charge? Why should a particle have a charge?
1
vote
1answer
50 views

Does charge distribute itself uniformly on a conductor?

An excerpt from a beginning E&M book [...] In other words, the surface of a conductor is an equipotential surface under static conditions. [...] Summarizing the boundary conditions at the ...
1
vote
1answer
67 views

Understanding EM Fields

I am an electronics engineering major and some questions arise when studying communications technology that utilizes wireless technology. In particular, I am more of a complete picture kind of person, ...
2
votes
3answers
81 views

Potential energy & entropy of three particles

Let me first say that I am not a physicist, but I am trying to make a simulation on my computer and I have the following question. Let's consider that we have three free charges that somehow can ...
3
votes
0answers
134 views

Free charge movement in an electric field - including bremsstrahlung

Let us imagine a free, negatively charged object that is in rest and placed in an elecric field of a point positive charge. The positive charge has a huge mass and cannot move, so we consider only the ...
0
votes
2answers
47 views

Charge Distribution in Reissner-Nordström Black Holes

In an electrically charged black hole, such as the one described by the Reissner-Nordström metric (i.e. with no angular momentum), where would the electric charge be situated (neglecting any charged ...
3
votes
3answers
227 views

How to understand “accelerating charge radiate” using intuition? [duplicate]

While I know that accelerating charges produces EM radiations (at least in lots of cases), most discussion about this matter only focuses on which kind of situation will emit EM radiations and which ...
0
votes
1answer
37 views

How does a minority carrier diffuse?

I have gone through a lot of questions but none of them ask how do the minority carriers approach the depletion layer in the first place. When a p-n junction is formed, negative space charge ...
3
votes
1answer
80 views

A question about the Thomson experiment

Recently, I was studying about Thomson's experiment with cathode rays. My textbook shows it like this. It says: When only electric field is applied, the electrons deviate from their path and ...
2
votes
2answers
39 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 ...
1
vote
1answer
59 views

What gives an elementary particle a charge? [duplicate]

We know that proton is positive, and electron is negative. But where does come notion of negativity and positivity? Does charge come from some specific particles, or they specific order?
0
votes
0answers
33 views

Variation of Electrostatic Potential with Distance in a Uniform Field

I came across this question in a problem book: If a proton is released from rest in a uniform electric field, does the electric potential at those points where the electron moves increase or decrease. ...
0
votes
2answers
32 views

Can a negative charge ionize air?

Can a negative charge ionize air? Adding to this question, I have studied that positive charge ionizes air but never studied that negative charge ionize air. If possible, please explain how does it ...
3
votes
1answer
112 views

Why is charge not taken as a fundamental unit? [duplicate]

According to the definition of electric current, it appears to be a derived quantity. Charge on the other hand seems more fundamental than electric current. Then why is current taken as fundamental ...
1
vote
2answers
47 views

Charge inside a sphere

Suppose I have a sphere of radius $r$ with all the charge residing on the surface, distributed uniformly i.e. charge density $\sigma$ is constant. I want to find the electric field created by this ...
1
vote
1answer
74 views

Upper limit to electric charge confinement?

The following questions are not intended for conventional capacitors (which stores excess charge on the outside surface), rather a type of hypothetical capacitor which is designed to confine charge by ...
4
votes
3answers
177 views

What exactly is charge? [duplicate]

If gravity is really the bending of space/time causing objects with mass to experience acceleration, is there a similar physical meaning to 'charge' besides 'a property of matter which causes it to ...
0
votes
2answers
34 views

Which charge value to use and Why [closed]

$1\mu C=10^{-6}C$ vs $e=1.60\times10^{-19}C$. I am having trouble understanding when to use for $q$, $10^{-6}C$ or $1.60\times10^{-19}C$. I had a problem where $a=Eq/m$. I don't know which value of a ...
1
vote
0answers
36 views

What would happen if…? (Scenarios involving a ball in an electric field) [closed]

First I shall define two table tennis balls: Ball $A$ is coated with a conducting material and ball $B$ is an insulator. Then I'll define two scenarios: Scenario $I$ is a ball held from a ...
3
votes
1answer
47 views

Do electrons move in a conductor when it is connected to only one pole of a power supply?

If I were to get a conductor e.g. a piece of copper wire or aluminium and connect it to one pole of a battery (let's take the positive pole for example), will electrons be removed from the conductor ...
0
votes
0answers
14 views

Questions regarding rubbing catfur on glass

I have certain questions regarding the electrostatic charge developed by this rubbing effects: 1-what is the threshold for electrostatic charges by this process? 2-can we define potential energy ...
0
votes
1answer
32 views

What molecules are ionized in a lifter ion engine?

Lifters generate lift through ionizing air molecules and then attracting those ions toward an oppositely charged surface to create thrust. are constructed on a balsa frame with a 1 inch wide aluminum ...
0
votes
1answer
36 views

How is the charge concentrated at the centre of shell for calculating potential from it?

While calculating electric potential due to a spherical shell at a point outside the shell, why do we say that the entire charge is present at the centre of shell? Is this true even if the charge on ...