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 ...

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According to Ohm's Law, shouldn't there be a zero electric potential within a capacitor since the current is 0?

If V = I*R, then how does a capacitor store electric potential? The current across a capacitor is 0.
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7 views

Charge distribution on a line

Given a conducting line segment from -a to a, with a total charge Q distributed by the continuous charge density $\lambda(x)$. I can write this system of integrals. Since the charge must total Q: ...
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1answer
2k views

Capacitance of two non parallel plates

What is the formula for capacitance of two non parallel plates at an angle with each other?If the plates were parallel then the value can be calculated as (PermittivityX area of one plate)/distance ...
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2answers
109 views

Why is the potential energy of a dipole in an electric field zero when the dipole points perpendicularly to the field?

I have read that potential energy of a dipole in an electric field is taken to be zero at 90 degree as they say that it is a reference. But there must be some reason behind it?
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1answer
178 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
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0answers
9 views

Flux through a face of a cube for an arbitrary position of a charge

Consider an imaginary cube with edge length a in space. A charge q is placed at the centre of one of the faces of the cube. So, what is the electric flux through the face opposite to the charge? ...
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0answers
34 views

Electric Filed on a point on a sphere [on hold]

I really want to understand the concept of those problems. Thanks.
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1answer
53 views

Saving energy while charging capacitor

While charging a capacitor by a DC source, half energy is wasted as heat. Can't we save that energy? Here I am talking about $$1/2CV^2 $$ which is wasted while supplying $$CV^2$$
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4answers
287 views

What will be final velocity of three charges $q$, $q$, $2q$? [on hold]

What will be final velocity of three charges q, q and 2q kept along an eqilateral triangle of side r at infinite distance. All three masses are equal. I tried to conserve Total Energy ...
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2answers
84 views

How does magnetism work? (Not asking what magnetism does)

To clarify, if I asked "how does electricity work" I would want "electrons flow from a negatively charged area to a positively charged area", not "it powers electronics like phones" as an answer. The ...
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1answer
37 views

Does the electron's electric field strength differ when bounded to a nucleus from the strength in a free state?

Since in any material the nucleus is surrounded by electrons some of the electron's electric field does interact with the other electrons from the same atom and with the electrons from the surrounding ...
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2answers
406 views

How to find the distribution of charge on two spheres connected by a conducting wire?

A solid metal sphere of radius $R$ has charge $+2Q$. A hollow spherical shell of radius $3R$, concentric with the first sphere, has net charge $-Q$. What would be the final distribution of the charge ...
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5answers
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Why is electric potential scalar?

I can't conceptually visualize why it would be so. Say you have two point charges of equal charge and a point right in the middle of them. The potential of that charge, mathematically, is proportional ...
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1answer
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calculation od stacked plate capacitor capacitance [on hold]

how we calculate the capacitance of a stacked plate capacitor ? is it the summation of the capacitance of each capacitor $Ci$ ?
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2answers
598 views

How does the magnetic field get induced in car's tire?

I was amazed to see how my car's tire started attracting the nuts and bolts, how in the world did it induce the magnetic field? Never heard of such phenomena!!!
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1answer
648 views

Apply Gauss' law to find electric field around nonconducting plastic sheets

The question: Two very large, nonconducting plastic sheets, each 10.0 cm thick, carry uniform charge densities $\sigma_1$,$\sigma_2$,$\sigma_3$ and $\sigma_4$ on their surfaces, as shown in the ...
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0answers
9 views

Conformal transformation for a vertical strip at constant potential

Say I've got a vertical strip in the $xz$-plane running from $x=0$ to $x=a$ held at a constant potential $V_0.$ The whole of the $yz$-plane is fixed at zero potential. Now I want to find the potential ...
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2answers
20 views

Will there be a potential difference between two conductors if there is same charge between them but the magnitude of charge is different?

By same charge I mean that same nature of charge i.e " Both positive or Both negative " . To be more specific consider two plates both of the plates are held face to face close to each other much like ...
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6answers
105 views

When we write that $F = -\nabla V$ , what would happen if we ommit the (-) minus sign

I have had this question for a long time. In classical mechanics, if we choose $\mathbf F = -\mathbf \nabla \, V,$ with the minus sign, we can proof the work - kinetic energy theorem. What are the ...
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0answers
13 views

Finding the value of E at a point in a 3D field with 2 separate point charges [on hold]

Having some trouble with this question: A charge 30 nC is situated at the point (x, y, z) = (0, 2, 0) and a charge of –30 nC at the point (0, -2, 0) m. Find E at the points: (a) A = (4, 2, 4) m
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2answers
33 views

Some Clarifications about Electricity

In the diagram below (ignoring the text), does the $V$ mean that there is some electric field outside of this system which results in a potential difference of $V$ between $a$ and $b$ or does it mean ...
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0answers
29 views

Coulombs Law on Quarks [closed]

As from opinion from others the question don't seem to be clear so I did some changes. What is 5.33... it is 5+0.3+0.03+0.003+.... this sequence does not ends. now if we have a ball and we need to ...
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3answers
46 views

Is it possible to avoid static electricity? [on hold]

Sometimes I touch a car or a door and I feel the static electricity in my hand and it hurts sometimes. I try not to touch anything because I feel like I am going to feel this pain again. Is there a ...
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1answer
121 views

potential inside a cylindrical shell in terms of the surface potential?

Given a potential distribution $V(\phi)$ at the surface of an infinite cylindrical shell, is there an easy way to derive the potential inside the cylinder. No charges or currents anywhere.
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2answers
28 views

Why is the electric potential of a point from a point charge of +Q positive?

According to the formula, $$V = - \int \vec E \cdot d\vec r.$$ The electric potential of a point charge is $\frac{KQ}R$? However, when I perform the integration, my answer is $-\frac{KQ}R$. Since ...
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2answers
1k views

Meaning of boundary condition for steady current density?

Although I understand the derivation of boundary condition in case of steady electric current but I did not understand, that the electric field which is in direction of $J$ current density that is ...
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2answers
51 views

How does a point charge interact with a Gaussian surface?

A spherical Gaussian surface encloses a point charge $q$. The point charge is moved to to a point away from the center of the sphere. Does the electric field at a point on the surface change? ...
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0answers
36 views

How did I get these strange electric shocks? [on hold]

While doing experiment on designing & fabricating temparature controller circuit using a thermistor, this strange thing happened.Me & my friend frequently experienced short pulses of electric ...
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2answers
77 views
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1answer
31 views

Why is resistance equal to the Voltage over the flowing current? [closed]

I can never understand these types of questions: questions based on definitions. So resistivity of a substance is defined as the voltage provided over the current flowing. But, my first question: ...
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2answers
665 views

Why does electric force depend on the medium?

Comparing the equations for the gravitational and electric force $$\vec{F}_g=-\frac{Gm_1m_2}{r^2}$$ and $$\vec{F}_e=\frac{Kq_1q_2}{r^2}$$ I noticed the only major difference between them is that ...
2
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1answer
47 views

Electric Potential due to Sphere when cavity is at arbitrary position [closed]

While doing practice question, I came across a question... A solid sphere of radius a has a cavity of radius b which has a uniformly charge distributed with density $-\rho$ and the remaining part ...
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2answers
25 views

How is electric field effected by loss of energy of charge?

Recently, I asked a question related to energy of a charge(This is the question). In one of the answers, in the comments section, I got an answer that the strength of the electric field is lessened ...
2
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1answer
142 views

Physical interpretation related to a non-linear partial differential equation

I am doctoral student in pure mathematics working on a particular problem. My question is if this problem has applications to real world phenomena. I will try to explain the direct problem starting ...
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1answer
134 views

Is putting a charged balloon up to a neutral wall polarization AND temporary induction, or just polarization?

Is putting a balloon that is charged up against a wall and having it stick polarization AND charging by temporary induction, or just polarization?
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3answers
361 views

Why may an air passenger experience an electric shock when he touches the door knob of the toilet of an aeroplane flying at a high altitude?

Why may an air passenger experience an electric shock when he touches the door knob of the toilet of an aeroplane flying at a high altitude?
3
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3answers
53 views

If the entire potential energy of the charge is lost within the circuit, what happens to the charge?

This is a really confusing question for me. Suppose, there is an electric circuit. And, right near to the negative terminal of the battery, I place 3 bulbs, which would take almost all the energy of ...
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0answers
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2answers
174 views

Two charged spheres connected with a conductor

I have a problem with a electrostatics problem: there are two spheres, each one of the same size carrying the same amount of charge, but of different sign. They are connected by a conducting wire, ...
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1answer
46 views

Figuring out the orientation of a dipole and its distance from a point charge

The problem assigned is this: A dipole is centered at the origin of a coordinate system, and a small charged sphere is some distance away along the perpendicular bisector of the dipole. The particle ...
0
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1answer
83 views

Two concentric conducting shells connected by wire with modified Coulomb law?

This question is related to this one, but is a bit different. Consider two concentric and conducting spherical shells connected by a wire. Inner shell has radius $b$ and (unknown) charge $q_b$ while ...
2
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0answers
45 views

Gauss' Law and Electric Field Close to a Ball

So I've learned about Gauss' law and I have something in my head. Why does electric field that is very close to a ball is not close to infinity. Take a look at this image: As we can see, if we make ...
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1answer
29 views

boundary condition of electrical field

The boundary condition of electrical field is well known. $$ E^{\perp} _{above} -E^{\perp} _{below} = \frac{\sigma}{\epsilon_0}$$ Griffiths wrote that where there is no surface charge $E^{\perp}$ is ...
2
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2answers
3k views

The electric field of a conductive sphere containing a charge - grounded vs not grounded

Let's suppose we have a sphere but unlike theoretical ones it'll have some thickness say $\Delta r$ and inner radius $R$. What I was wondering about is how will it behave if we place some charge $q$ ...
3
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2answers
102 views

Charging by induction [closed]

When we charge an conductor by induction and grounding, we first bring a negative charge to the conductor. As a result the mobile electrons of the conductor get repelled and stay far from the negative ...
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2answers
313 views

Should the electric potential of a positively charged sphere be negative?

Because the indefinite integral of the electric field results in a negative value? (As the function is proportional to $r^{-2}$? I've got to be missing something... Help please!! Thanks! Also, I ...
0
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1answer
4k views

Potential energy of the dipole-dipole interaction for two parallel dipole moments

I am looking for an equation that gives me the potential energy of the interaction between two parallel dipoles.
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0answers
24 views

Problem in electrostatics [closed]

I tried a problem in electrostatics. In which I emplyed two different methods to find the electric field inside a solid cylinder of charge distribution having density ...
1
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2answers
62 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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0answers
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Gauss law-electric field through the spherical surface of a sphere [closed]

FIND THE WORK DONE IN MOVING A POINT CHARGE Q=10 MICROCOULOUMBS FROM THE ORIGIN TO A POINT(4,pie/4,pie/2)SPHERICAL COORDINATES IN THE FIELD E=5e^(-r/4)+10/(rsinx)