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Charge distribution: electrostatic equilibrium in conducting sphere

In the hollow interior of a conductive sphere, we can create the same type of unstable equilibrium situations that we know from empty space. For instance two positive point charges $q$ and a third one ...
Jos Bergervoet's user avatar
1 vote

Could you calculate the force between two NON-PARALLEL, straight current carrying wires?

Assuming we already know how to calculate the $B$-field of one infinite straight wire, we only need the integral of its force over the second wire. Without loss of generality we can assume that the ...
Jos Bergervoet's user avatar
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How does charge move in conducter which is between two connected conductors

You can treat this as two parallel capacitors. One between the top plate and the top of the middle plate, and one between the bottom plate and the bottom of the middle plate. Since the dielectric ...
The Photon's user avatar
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Why do charges uniformly distribute themselves on the surface of a conducting sphere with a charge inside its cavity?

A very simple answer is follow the logic: It's undeniable that the charge q in the cavity attracts electrons in the conductor to the surface of the cavity. These electrons repel each other so they ...
Obliv's user avatar
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1 vote

Why is there a band gap in semiconductors but no band gap in conductors?

The reason is that in semiconductors the valence electrons form chemical bonds between neighbouring atoms, while in conductors the valence electrons only collectively bind the atoms together by ...
my2cts's user avatar
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1 vote

Charge Inside a conducting hollow sphere

The electrons in the inner sphere will rearrange themselves so as to shield the inside from any static electric field produced by charges outside it. The electrons in the outer sphere will also do the ...
Brian Bi's user avatar
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1 vote

Charge Inside a conducting hollow sphere

The net electric field inside the inner conductor will be zero. You are correct there. The electric field outside the inner sphere and inside the outer sphere (R1<r<R2) will be non-zero. The ...
Devansh Mittal's user avatar
2 votes

Charge Inside a conducting hollow sphere

Since the problem's geometry consists of two concentric spheres, one can apply Gauss' law, $$\oint_S \vec E\cdot n\;dA={Q_{enclosed}\over \epsilon_0};$$ to great effect in analyzing the electric field ...
Albertus Magnus's user avatar
-1 votes

Electric displacement field in a conductor

This is a result of the electrostatic balance of a conductor. First, it is obvious that $\mathbf{E}$ inside the conductor is zero, because any tiny electric field will cause the motion of the free ...
见习光系法师's user avatar
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Electric displacement field in a conductor

I think that in this case it can be quite useful to revisit the microscopic interpretation of polarization in classical electromagnetism. In a dielectric material with no external electric field we ...
Truth-Beauty-and Hatred's user avatar
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What is the electric field inside a perfect conductor connected to a DC source?

"Now imagine the same perfect conductor is connected to a DC voltage source by "perfectly conducting wires." That is called a short circuit. There will initially be a huge electric ...
Jerrold Franklin's user avatar
1 vote

Why force by electric field is appearing?

The Lorentz force creates makes for an excess of positive charge at the top (ceiling) of the wire (electrons travel up from the floor to the ceiling of the wire). At equilibrium: Lorentz force pushes ...
Daniel's user avatar
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-1 votes

Electric displacement field in a conductor

My original answer was wrong, so I am replacing it with this answer (in Gaussian units), which I believe is correct. In a dielectric with a permanent polarization, $\bf P$, any electric field will ...
Jerrold Franklin's user avatar
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Charge distribution on a torus (doughnut) shaped conductor

Here, Gauss law is a special case of Maxwells electrostatic equation $$\nabla \cdot \vec E =\rho$$ at a conducting surface with constant potential U along the two tangent directions, yielding $$\vec n ...
Roland F's user avatar
3 votes

Electric displacement field in a conductor

I believe the questions stems from viewing $\vec{E}$ and $\vec{P}$ as independent. But $\vec{P} = \epsilon_0 \chi \vec{E}$ Thus: $\vec{D} = \epsilon_0\vec{E}+\epsilon_0 \chi \vec{E}=\epsilon_0 (1+\chi)...
Daniel's user avatar
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Electric displacement field in a conductor

The polarisation field, at least in linear materials, is proportional to the electric field. The electric field is zero in an ideal conductor and thus so is the polarisation field. Note, there is no ...
ProfRob's user avatar
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4 votes

Would seawater flow be affected by a magnet?

There will be weak diamagnetic and Lenz's Law effects, and a small Faraday voltage will be generated across the stream. Magnetic flow meters work by measuring this voltage. The flow velocity might be ...
David Bailey's user avatar
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Would seawater flow be affected by a magnet?

Since the water is streaming, moving the magnet does not change the physical situation (unless you move it at the 'average speed of the water' and so we suppose you don't) Now you have positive and ...
Confuse-ray30's user avatar
2 votes

Understanding Kirchhoff's first law in charged conductors

There is a way to state KCL without stipulations regarding charge accumulation. Rewrite the continuity equation (or take the divergence of Ampere's law) to get $$\mathbf\nabla\cdot\left(\mathbf j + \...
Puk's user avatar
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2 votes

Understanding Kirchhoff's first law in charged conductors

You are correct, Kirchhoff's circuit laws only apply when the lumped circuit approximation is valid and one of the assumptions of the lumped circuit approximation is that no charge accumulates in the ...
The Photon's user avatar
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