Electrostatics is concerned with the electrical fields and scalar potentials of stationary electrical charges and charge distributions. Use this for questions about electromagnetic situations in which currents and magnetic fields are absent, otherwise use [tag:electromagnetism] and/or ...

learn more… | top users | synonyms

-1
votes
1answer
89 views

What exactly is electric dipole moment & how it works?? and Why Electric Dipole Moment vector's direction is from negative charge to positive charge?

What exactly is electric dipole moment & how it works/used? (don't go into deep mathematical calculations) Please answer the question about the direction with good details. Don't just say that ...
2
votes
2answers
1k views

Why the electric potential of earth is zero?

For a localized charge distribution the potential is set to zero far away from the charge distribution (at infinity) Now, when grounding a conductor, i.e. connecting it to Earth, it is said that we ...
0
votes
1answer
22 views

Potential of 2 parallel plates

How can I write down a potential of 2 parallel plates (area $A$) with charge $+Q$, $-Q$ such that V(inf)=0 and V(in) is what I would expect, $Ed = Qd/A\epsilon_0$. Do I have to write a discontinuous ...
1
vote
1answer
40 views

Does wearing jewelry increase chance of static electricity

I am the only one in my office repeatedly subject to static stock. Does wearing silver jewelry increase my chance of getting a shock?
4
votes
2answers
86 views

How to get the electric field strength of a plate as approximation of a sphere

Suppose you know that the electric field in distance $r > R$ from the center of a charged sphere with charge $Q$ and radius $R$ is given by: $$ E = \frac{1}{4\pi\epsilon_0} \frac{Q}{r^2} $$ ...
0
votes
1answer
30 views

2D room with electron-point-charges (stability)

Is there a fast way to find out stable #"point charges" & constellation for this kind of Simulation. The 2D repeating itselve in each direction till infinity, so i've a kind of symetrie here. ...
3
votes
4answers
2k views

Is an electron/proton gun possible?

In the 1944 SF story “Off the Beam” by George O. Smith, an electron gun is constructed along the length of a spaceship. In order to avoid being constrained by a net charge imbalance, it is built to ...
2
votes
3answers
471 views

How much energy is needed to create an electron?

I know how to calculate the electrostatic energy of a sphere (it has a well defined radius). But how can I calculate the electrostatic energy of an electron as it is a point particle? By electrostatic ...
1
vote
0answers
27 views

Interaction between charged particles through static electric fields [duplicate]

I generally find it pretty primitive to accept that static charges communicate with the help of static electric fields without any exchange going on between them such as electromagnetic waves. I ...
2
votes
1answer
80 views

Can an electric field align water molecules?

Water is a polar molecule, which means it has an uneven charge distribution. How much of an electric field strength would it take to align all, or most, of the molecules at room temperature?
3
votes
1answer
173 views

Need of small charge in definition of electric field?

Why do we need infinitesimally small charge in definition of electric field? Since the test charge cannot exert force on itself, F on test charge will not change whatever the value of test charge q ...
0
votes
0answers
30 views

Nylon vs PVC triboelectric series

If we charge a nylon rod and a PVC rod using friction, and discharge them individually to a metallic object to measure how much charge they can tranfer, it can be seen that the charge taken out by the ...
2
votes
1answer
224 views

Where can I find a database for dielectric constants in the visible range?

I am looking for a database of dielectric constants in the visible range and I could not find them by Googling, so I was wondering whether anybody here knows where I can find those parameters for some ...
1
vote
3answers
8k views

Determine Charge With Electroscope?

You have three separate glass rods, and you know one is positive, one is negative and one is neutral. You also have an electroscope that is positively charged. How can you determine which rod is ...
0
votes
2answers
221 views

Do glass beads show any piezoelectric property?

Do glass beads show any piezoelectric property? Since glass beads is mostly made out of SiO2 which is piezoelectric, will it show any piezoelectric property. Thanks. If anything wrong with my ...
0
votes
2answers
418 views

Electric potential inside shell

Suppose we have a hollow neutral shell and $q$ charge at $r$ from its center now we take a point a someplace other than center then will electric potential change? I don't think because electric ...
2
votes
3answers
11k views

How can I theoretically describe the potential between two capacitors in series?

Suppose to have two capacitors in series: The voltage in the middle point will be: $$ V_X = V_1 \frac{C_1}{C_1+C_2} $$ How can this be explained? It's been asked in electronics, and explained in ...
1
vote
4answers
1k views

when we rub objects together, what determines which material will pick up electrons?

For example We know glass when rubbed by silk will become positively charged while the silk will be charged negative. What exactly makes glass appropriate for losing electrons in that experiment? (
0
votes
3answers
57 views

How can we assume that we're in electrostatics if we are talking about current?

In the textbook I am currently reading it states that to even out the flow of current throughout a circuit, the force required is of the form $f=f_s+E$ where $f_s$ is from the battery or other energy ...
1
vote
5answers
127 views

Physical interpretation of the statement $\oint E\cdot dl=0$

Can anyone provide me with a physical interpretation of $\oint E\cdot d\ell=0$ in electrostatics?
1
vote
2answers
89 views

Does zero change in magnetic flux always imply zero emf induced?

If you have a uniform B field, with a finite piece of wire inside it. Assuming the B field spans all space and the wire cannot leave the field. Are you able to create an emf by moving the wire ? I ...
0
votes
1answer
34 views

Question regarding 2 conducting spheres connected by a long fine line (electric potentional)

I'm having a bit of trouble understanding a pretty simple issue. Assuming I have 2 conducting spheres uniformly charged connected by a long fine line (as shows in the added photo) and im being asked ...
0
votes
0answers
35 views

How to prove that the electric field strength in the interlayer is radial?

This is a structure modified from a typical metal spherical capacitor: half of the interlayer is now filled with one kind of uniform, isotropic, and linear dielectric medium whose dielectric constant ...
0
votes
1answer
73 views

Charge inside a shell

There's a positive charge Q inside a neutral conducting shell. An external field is applied. I learned that there can be no effect in cavity due to external things (electrostatic shielding), so ...
2
votes
2answers
61 views

Is there such thing as an evenly-charged sphere?

Let's begin with a very typical model seen in almost every electromagnetics textbook: a solid, evenly-charged sphere. First it cannot be a conducting sphere because charge will automatically ...
0
votes
1answer
205 views

Circuit breaker Trips during thunderstorm

The circuit breaker at the electrical mains trips at home when there is a thunderstorm outside. Why does this occur?
4
votes
3answers
1k views

Why is surface charge distribution uniform for a conducting sphere? Can't it be arbitrary?

If the charge $q_1$ has to repel the charge $q_2$, the electric field has to go inside the conductor which contradicts the fact that electric field inside conductors is zero. Then why do the charges ...
0
votes
1answer
40 views

Preventing Electricity Leakage With Insulators

If we charge an object made of insulating material, the charges on it would leak to the medium as the time passes, due to the potential difference. I would like to know if there is a way to prevent ...
8
votes
2answers
1k views

Can two electrons never touch each other?

The Coulomb's force is given by $$ F = {k q^2 \over r^2} $$ When $ r \rightarrow 0 $, $ F \rightarrow \infty $ Does this mean two electrons never touch each other?
0
votes
0answers
65 views

Electrostatic ion thruster neutralizers

All electrostatic Ion thrusters have a neutralizer electron beam, but why are they required? Is avoiding the accumulation of negative charge the only reason? I would've thought that the main reason ...
0
votes
1answer
41 views

Any economical quantitative electrostatics experiments for the university level?

I'm seeking for some safe experiments for undergraduates in the electrostatics context. We have a Van-de-Graaff generator in our fundamental physics lab but this kind of devices are useful for ...
4
votes
2answers
681 views

What is charge actually? How to define it? [closed]

Is charge of something for (e.g.) an electron related to electromagnetic space if it exists due to energy, due to which it may have mass? I don't know about quantum mechanics or advanced particle ...
1
vote
1answer
53 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
0answers
22 views

Approximating electrostatic grids as a multipole expansion

Is there a known good summary, or a succinct algorithm to compute the far-field approximations of an arbitrary set of electrostatic surfaces set at different potentials? I'm looking to model a ...
0
votes
2answers
55 views

Is that ground, wall conductive?

If i put my foot exposed to ground and put my finger to the USB power, i will be electrocuted. So the electron(s) from the USB power is passing over my hand, run to foot and go to ground ? As i might ...
1
vote
1answer
144 views

The advantages of a dielectric in a capacitor

In a capacitor a dielectric can be placed in between the two plates. I have trouble understanding the points / advantages of a dielectric from what I have read in a text book. The points written there ...
0
votes
1answer
48 views

A query regarding constant $\frac{1}{4\pi \epsilon_{0}}$ in Coulomb's Law [duplicate]

In our physics class we were discussing about Coulomb's Law and equation for the electrostatic force between two points: $$F_{e}=\frac{Q_{1}Q_{2}}{4\pi \epsilon_0 r^2}$$ From the equation a query ...
0
votes
1answer
37 views

electric charges of metals in electrostatics

In electrostatics does metal gain electrons to be an ion or it conduct electrons in form of gaining them to have a negative electric charge
0
votes
1answer
39 views

Electric Field Contributions

Figure 1: Two thin parallel wires Figure 2: The cross section of a hollow sphere containing a smaller, hollow sphere The electric fields for both figures are calculated using different principles. ...
1
vote
3answers
833 views

Parallel-plate capacitor

I'm trying to grasp parallel-plate capacitors in a class of electromagnetic field theory. My book leaves out a lot and I couldn't figure it out from what I found on Google. The book's procedure is ...
0
votes
1answer
43 views

Influence of a Capacitance Matrix of a voltage measurment

I am having a problem in understanding how in a multiconductor system the Capacitance Matrix influences the measure of voltage between two electrodes. In the case that interest me we have 4 ...
0
votes
1answer
125 views

Electrostatics of Conductor

In an isolated conductor the extra positive or negative charges will be distributed on the surface uniformly. Hence there will be no charge inside the conductor, hence no field. But what accounts for ...
4
votes
1answer
132 views

Flashing a fluorescent light bulb with high voltage

My son and I built a Wimshurst machine (our second try) over the last couple of weekends. It works -- not terribly well, as it only makes 2cm sparks with 20 cm disks (something like 60 kVolt when it ...
0
votes
2answers
65 views

Is electric potential a form of potential energy?

As I understand it, the concept of potential energy arises from analytical mechanics. Yet I often see the concept of electric potential $\phi$ introduced without mention of analytical mechanics. For ...
2
votes
1answer
31 views

Modelling ions hitting a grid

I want to model the capture of ions by a negatively charged grid made of some proton conductor material like graphene oxide. Are ions captured as soon as they cross the surface, or do they have some ...
-2
votes
1answer
90 views

Gauss' Law - Parallel plates [closed]

A parallel plate capacitor with dielectric (as above), together with its dimensions. Its plates are square. The capacitance is given by the usual formula, $C = \frac{\epsilon _0 \epsilon _r ...
10
votes
6answers
1k views

Paradox with Gauss' law when space is uniformly charged everywhere

Consider that space is uniformly charged everywhere, i.e., filled with a uniform charge distribution, $\rho$, everywhere. By symmetry, the electric field is zero everywhere. (If I take any point in ...
0
votes
2answers
45 views

Charging a spherical capacitance

How could one charge a spherical capacitor with a battery or any other emf source?
2
votes
2answers
209 views

Energy Stored in a Capacitor with and without Dielectric

I have seen the equation $V = \frac {V_0}{K}$, but also the equation $V=\frac{1}{2}CV^2$. The values of C and V increase in the same linear ration with K (because $C=KC_0$). However, as the energy ...
0
votes
1answer
29 views

Ability to discharge static electricity

Ever since I was a child, I have been able to "discharge" static electricity in clothing by touching it. The static falls out immediately! As a child my mother would have me touch all the laundry ...