Questions tagged [electric-fields]
For questions that utilize the concept of electric fields (commonly denoted by the letter E), or for questions whose answers likely involve electric fields. More specific than the [electricity] tag, as questions about the phenomenon & theory of electricity do not necessarily involve the discussion of fields.
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Is the voltage a result of the existence of the electrical field or is it vice-versa?
Sorry for my question that may be a bit vague but
In my school book there are these two definitions:
The direct current results from the movement of free electrons so the overall movement be in one ...
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Electron gun; potentials around charged plates
I know that an electron gun releases electrons by thermionic emission and accelerate the electron through charged plates, and that the electrons are not gaining any energy after they leave the gap ...
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Why electric field increase near the cable connected in AC 220V socket even current is zero?
If I put low frequency electric field meter near the connected cable in AC 220V socket, he show 1200 V/m even if device is turn OFF(zero current), if disconnect cable from socket, field drop to 8 V/m.
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How will the capacitance of a capacitor reduce when the distance between the plates is increased?
Now I know that if the potential difference between the plates increase that capacitance will reduce, but for that also I thought as the distance between the plates increases, the electric field ...
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Understanding dielectrics on the basis of induced charge and energy density
Simply, why is the energy density in a dielectric medium = $\frac{1}{2} K \epsilon_o E^2$?
For a simple case such as that of a capacitor with a dielectric medium inside it, to find the magnitude of ...
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How is the index notation for the electromagnetic potentials defined?
I don't understand, how the $\vec{A}$ potential is defined in the covariant formulation of the Maxwell-Equations.
I am using the metric $(+,-,-,-)$.
The electric field (SI-Units) is defined as:
$$
\...
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Work done on a charge inside a homogeneous electric field and changes in Energy of the system
How to understand the concept of work using the following example:
a positively charged particle (with charge $Q$) is placed in between a charged in a homogeneous electric field between the capacitor ...
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Does the geometric shape of the cross-section of an infinitesimally thin conducting charged thread (wire) affect its electric field?
Assume that a solid conducting torus (toroidal ring), with a cross-section of a circle of (minor) radius $r$, is negatively charged. Solving Poisson's equation, we can find the charge distribution of ...
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Diffusion current in semiconductor while applying an electric field
In case of intrinsic semiconductor, while applying an electric field, only drift current should exist, right? As diffusion current is due to concentration gradient. So the electron flow will be ...
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What is the electric field strength of a photon? In $\rm V/m$ or $\rm N/C$? Or its magnetic field in Gauss or Tesla? For visible light, or gamma rays? [closed]
I am thinking of this now because I have been learning about the Schwinger limit (or Schwinger effect)...
Supposedly, a strong-enough electric and/or magnetic field creates a 'nonlinear' effect in the ...
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Comparing Electric Potential Energy of two Charges
I do not know what I am missing here and would appreciate a little help in figuring out the flaw in my logic. I have a row of positive charges and a row of negative charges as shown in the image above....
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Electric field outside of a conductor with charge $q$
Suppose that I have a spherical conductor (radius $R$) with a cavity at the center and a charge $q$ inside it. I know that the electric field outside of the conductor will be
$$\vec{E}=\frac{q}{4\pi\...
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Electric field outside a conductor
Say there is a conducting cylinder in a uniform external field. The charges on the cylinder surface will distribute and create a surface charge density.
Is there any reason the charge density would ...
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Textbook question on calculation of potential difference between two points
My textbook has the following question
What is the potential difference between two points that are 50cm and 80cm respectively from a point charge of 2uC?
Unfortunately, the textbook has not taught ...
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Electric potential derivation
The definition of electric potential is the work done per unit charge in moving the charge from infinity to that distance.
Now, from Coulomb's law,
$$F = \frac{KQ_1Q_2}{r^2}.$$
So we can now rearrange ...
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