Questions tagged [electric-field]
The electric-field tag has no usage guidance.
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Electric field of line charge and coaxial conductor
I'm currently having trouble understanding why the electric field inside a coaxial conductor (assuming that the charge is evenly distributed on the inner and outer conductor and opposite signed) is ...
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Estimate susceptibility of circuits to external electrical field strength
I will be soon testing a product to an electric field spectrum requirement (i.e. in the 100's of dBµV/m vs MHz), and it shouldn't be a problem because of how small the values are compared to the ...
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Help with circuit for school
I am doing a project for school with two friends. We are going to make a DIY metal detector. We are using a source as our circuit. Can someone help us describe what is happening in the circuit?
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Finding resistance between two conductors
For my electromagnetic-field class we are asked to calculate resistance between two electrodes shown as below.
The part c(i) is just a simple resistance question using the formula R=pl/a.
I don't ...
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Is the field strength between 2 electrodes dependent in any way on the medium?
I want to apply a high voltage electric field to a particle. Provided the electrodes are at the same distance and relative location from the particle in any case, will it make a difference to the ...
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What is the electric field 𝐄ᵢ produced by the i-th source charge arranged in a line with equal distance between each other?
I would like to know what the electric field Ei is produced by the i-th source charge arranged in a line with equal distance between each other. Please see my calculations in the following three ...
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Calculate potential between two rods
Suppose we got four thin, long and parallell conductors with charges shown in the image below. Each conductor has a radius \$ r\$ and length \$ l\$ . Our problem is to find the potential between the ...
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What is a volt?
How a volt is measured and defined in the simplest terms? What does it mean when you measure voltage using a voltmeter? In the past, we defined things by physical things. For example, the kilogram ...
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Human body communication, magnetic vs capacitive coupling
I am reading a paper by Park and Mercier called Magnetic Human Body Communication (2015). They are looking into human body communication techniques and compare magnetic human body communication (mHBC) ...
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What are changes in field lines after two plates of capacitors are connected?
I recently came along to know about capacitors and their ability to store charges, also I studied about their electric field, I want to know what changes in electric fields will happen after we ...
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Antenna polarization and loss factor
I am trying to solve the following problem:
I know that in the +z direction:
linear polarization requires the field vector to have:
one component OR
two orthogonal linear components that are in ...
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Can you charge a capacitor with very high voltage and no or little current from secondary side of a step up transformer?
Based on the research I did online and after reading basic electrical books I understand that a capacitor stores energy in the form of electric fields. So I understand that, to charge a capacitor, all ...
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How does an electric field in a capacitor behave in an AC circuit? What does the E field look like for co planar capacitor plates?
Namely, is a "constant" E field changing direction at a rate of the applied frequency?
Does the E field in coplanar plates looks like this? Is there a way to derive the Capacitance of this ...
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How can I find critical field in tsmc65 transistor parameter?
How can I find critical field in tsmc65 transistor parameters? Critical field is the field which electron velocity in transistor go into the saturation region.
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Significance of electric field for electromagnetic compatibility standards
All electromagnetic compatibility standards around the world for immunity to electromagnetic fields (radiated susceptibility test) mention the strength of electric field (V/m), but not the strength of ...
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Why are the vertical deflection coils in a CRT deflection yoke so different from the horizontal coils?
Looking at a typical raster CRT deflection yoke, there appear to be two very different pairs of coils. There is the pair on the inside that curves outwards, and the pair on the outside, which are ...
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Why do we subtract horizontal and vertical component of a electric field?
I was solving a question of electrostatic which is: Find the electric field at a distance z above one end of a straight line segment of length L that carries a uniform line large lambda.
My question ...
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Contradiction in Gauss's law?
I have a question that my teacher was explaining but the question seemed to contradict the real world. I know it has got to be my understanding that is flawed but I cannot seem to get it. So here goes:...
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Which electrode configuration should have the highest electric field produced?
I'm currently simulating the the electric field produced by different types of electrodes.
The electric field is observed on the insulator that is sandwiched between 2 electrodes, one being 10 kV ...
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Why don't most electrons hit the anode in a cathode ray tube or electron gun?
In a cathode ray tube or electron gun, electrons liberated from the cathode by thermal emission accelerate towards a ring-shaped anode, from the potential difference between cathode and anode.
If an ...
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Converging Electric Fields on Metal Plate
I have a question, but I'm not a trained engineer, just curious. So bear with me on my explanation.
Let's say I have a metal plate.
I have DC power supply and I connect the positive electrode on one ...
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Finding the electric field due to a "point" dipole in different locations
I'm currently taking a course in Electrical fields and circuits and came across this example problem from the course book. I am having trouble figuring out how to solve it. Below you will find my ...
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Can there exist an arrangement of charge densities that creates a loop in the electric field lines of force?
Can there exist an arrangement of charge densities that creates a loop in the electric field lines of force?
In this answer, a poster writes:
Note 2 5/8: superconducting loop
A uniformly perfectly ...
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How to determine electric field polarity from electric field mill signal?
I have built an electric field mill like this, more info can be found in the (short) wiki article:
It works by exposing the sensing electrode to the ambient electric field, which (depending on E ...
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Electric field in a circuit and potential drop
With reference to the above image:
Here the battery produces a constant (will it be constant? pl. explain) electric field across the length of the wire, lets say its value is \$\vec E\$ . This field ...
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Is the strength of an electric field the same throughout a conductor connected to a battery?
Is an electric field the same all over a conductor?
As electrons move further in a conductor they start coming from high potential to low when moved from high potential end of conductor(cathode) to ...
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Best shielding material for a Faraday cage against 36kHz electric fields?
I have a room aka cuboid with 4 x 3 x 2.5 meters. In the 3D center is a device under test. To shield against 36kHz electric fields I want to build a Faraday cage.
I learned the hard way that aluminium ...
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Enhancing faraday cage
I have a room aka cuboid with 4 x 3 x 2.5meters. In the 3D center is a device under test. To shield against 36kHz electric fiels I have built a faraday cage by sticking 0,012mm thin and 30cm broad ...
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The equation of surface charge density is incorrect with only the sign is opposite of capacitor of cylinder form
The capacitor of the 2 cylinders exists.
As shown in the diagram, the righter space has been filled with the dielectric of \$ \epsilon_{1} \$ and the lefter space has been filled with the dielectric ...
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Cable shielding adequate for video, but not audio frequencies
I am no expert in audio equipment, but to educate myself I have been studying. In the process, I came across a video which tests the audio frequency shielding of a purported shielded video cable. (I ...
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How many newtons are there in one coulomb of charge?
Or, I should have said, how many newtons of force does one coulomb of charge exert? At a distance, presumably, of one meter? Since N/C is supposedly equivalent to V/m?
P.S. What are the values for a ...
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How can formal insulators "conduct" electric and magnetic fields?
Is there an explanation regarding the ability of an insulator between capacitor's plates to be permeable to an electric field?
The terms "valence band" and "conduction band" the ...
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What is the Relationship between Magnetic Flux density and electric field intensity
I was given this question by a teacher and I have scoured the internet for a formula or solution to this question, all to no avail, the question says
"in a certain region of space, the magnetic ...
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A DC current through a inductor does not create electric fields
While studying about electric fields and magnetic fields I came across this picture:
and this:
from this website and it indicates that there is an electromagnetic field around the loop of wire, ...
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Capacitor in presence of an external electric field
Let's consider a capacitor made of a couple of parallel metal strips (suppose they are made of perfect electric conductor) as shown in the figure, which represents a little capacitor.
Suppose an ...
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Gauss theorem on a finite sheet
I derived electric field at a distance z above and perpendicular to the centre of a sheet as
E =
Now i want to approximate the sheet as a point charge and derive the electric field . I am not sure ...
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Can electronic devices be installed on the pillar of UHV towers such as 345kV?
Can electronic devices be installed on the pillar of UHV towers such as 345 kV? Because I have an idea to install a remote automatic control electronic device on the tower to control the rotation and ...
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What's the logic inside the formula for the calculation of the maximal envelope modulation amplitude of two temporal interfering electric fields?
Since my question is a bit elaborate, I will first write some details. Thank you all!
I refer to the study conducted by Nir Grossman et al. (2017) about the use of the temporal interfering stimulation ...
user274494
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How to redirect electric field lines with a copper plane
I have been testing a capacitive sensing circuit in which an electric field is projected vertically to sense a finger (a grounded conductive object). On the PCB, a tx and an rx are 2 copper structures ...
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calculate force on object between capacitor plates without knowledge of area
I am given an exercise with a very simple circuit
simulate this circuit – Schematic created using CircuitLab
I am asked to find the voltage of the voltage-source V1 such that an object with a ...
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Signed or unsigned distance in electric potential due to point charge(s)
I am reading about the electric potential:
from wikipedia:
The electric potential (...) is the amount of work energy needed to move a unit of electric charge (a Coulomb) from a reference point to the ...
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Determining Electric Field on a Charge Plane
Question:
A plane \$x+2y=5\$ carries charge \$\rho_s=6nC/m^2\$. Determine electric field at \$(-1,0,1)\$.
My try:
At first, I calculated gradient
Let, \$\phi=x+2y-5\$
\$\begin{align}\\
\vec\nabla\phi&...
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How to measure the potential gradient between large capacitor plates?
I have built a capacitor for a biology experiment, but I need to measure the potential gradient between the plates. Mainly I am going to apply an AC current between the capacitor plates to have an ...
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Is the electric field in a wire constant?
If \$V=I\cdot R\$ according to Ohm's Law, that implies that \$\frac{\mathrm dV}{ \mathrm dx} = \frac{I \rho}A\$ across an infinitesimal length of conductor, which is constant at all points along the ...
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Electric field throughout a semiconductor
Suppose I have a semiconductor bar of length 2mm and I am applying a potential difference of 2V across it. Will the magnitude of electric field be same throughout the bar OR will it be different at ...
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