Questions tagged [electrostatic]
The electrostatic tag has no usage guidance.
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What is happening at the gate of a JFET to cause an electric field?
I am reading "Practical Electronics for Inventers" 4th edition and came across this circuit.
As I understand, for a JFET, current will flow from drain to source for a n-channel (opposite ...
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Verification of Electric Field from Infinite Line Charge
Problem:
I am currently tackling a problem involving the derivation of the electric field \$\textbf{E}\$ at location \$(0,y)\$ induced by an infinite homogeneous line charge \$\lambda\$ (refer to the ...
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Conformal Mapping in Electrostatics: t-plane
In the paper 'Extension of the application of conformal mapping techniques to coplanar lines with finite dimensions' the author uses the t-plane as a intermediate step for calculating the capacitance ...
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Electrostatic danger
At what is humidity the risk of electrostatic damage to electronics significant? Clearly 0% would be most dangerous and 100% would be less dangerous, but what are the risks in between?
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Troubleshooting a homemade Van de Graaff generator
So, I'm trying to build a Van de Graaff generator from household items, but after a lot of tries, I'm still unable to get it working and was hoping someone here could help.
The problem is that no ...
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Spherical capacitor properties
If we consider a spherical capacitor (having an inner conducting ring surrounded by another such conducting ring), how can charge reside on the inner surface since it's surrounded by another conductor?...
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Metal detector discrimination problem
I was experimenting with discriminating metal detector
I'm using TX coil about 28cm diameter, and 0.9mH with 470nF capacitor- pushing about 5Vpp sin wave from a signal generator
The RX coil also about ...
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Protect Arduino components from ESD damage from external input
I have an Arduino Due project that senses voltages through an ADC (ADS1115). The ADS1115 voltage sensor inputs will have intermittent connections. I have already fried my compass module by ESD and am ...
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DIY Van de Graaff generator
I have built a small Van de Graaff generator using items I found around the house, but I am unable to notice any charge accumulation on the dome. I was hoping you could help me troubleshoot the ...
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How to develop an ESD circuit protection
I am trying to solve what seems to be a common issue of the MAX232 chip getting burned by electrostatic interference. To solve this issue alternative chips are available on the market such as the ...
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Electrostatic transfer in wires
See illustration above.
I would like to know what happens if there is a wire between the static in the finger and an ESD senstive IC. What happens to the static in the wire or how does it behave in ...
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Potential static fault on chassis of system
The image attached is to demonstrate the observed behaviour. As the robot nears the push pads to charge, it moves its actuators down to make contact and as the contact is made the internal computer ...
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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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why does voltage drop across a resistor
I have seen the explanations about the energy lost in from of heat, but that energy comes from the net reduction of kinetic energy of the electrons (reduction of current). More over voltage is a ...
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Charging by electrostatic induction in a new way. Will it work? Instead of connection to Earth I am connecting to another conductor
I am adding the figure of a conventional setup for electrostatic induction.
The drawn setup on paper is the special setup.
If you don't want to read whole description then just read the summary.
...
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How can a conductor have voltage without charge on it? Taking in electrostatics [closed]
What does it mean if the potential of a conductor is Kq/r which is at r distance from the charge q? How can a conductor having no real charge have some potential (which is here KQ/r)?
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Is it possible to shield a metal ball with electrostatic shielding, or any other way?
Is it possible to shield a metal ball by the electrostatic shielding such that metal ball doesn't suffer electrostatic induction?
There is an electric field present near the metal ball but I want that ...
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Charging by electrostatic induction
In the given figure, if we connect the positively induced side of the sphere to the earthing instead of connecting it to the negatively induced side, then will the sphere get negatively charged ...
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Why does a capacitor plate connected to Earth lose charge?
Can you please explain this to me?
Is this correct? Why does the plate become neutral if the field outside the capacitor is zero?
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Does current flow from earth connected conductor in uniform electric field?
If we place a conductor inside of uniform external electric field then opposite charges will get induced on the both sides of conductor.
What if we connect two earth wire to each side, will continuous ...
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Generation of electrostatic induction
I need to generate a 500 volt electrostatic charge.
How can I do this?
I don't have a Van de Graaff generator.
What are some practical suggestions?
Basically I want to do an experiment in which I need ...
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Repelling charges and current flow
The electrostatic force between two like charges is repelling. This concept is fairly clear to me with Coulomb's law and electric fields. So two electrons will repel each other. Given this statement, ...
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Maxwell equation
$$
J = \sigma E - \frac{dD}{dt}
$$
I am having difficulties understanding this equation. I know that \$\small J = \sigma E\$ in the equation is a form of Ohm's law, but what is the other part?
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UART IO not working, placed multimeter to measure voltage and IO began working instantly - why?
We are a bit stumped on this and wanted to see if anyone had any experience or perspective on this.
Description of Event
We are communicating via UART from a 3.3V processor to a Sim7000G (1.6-1.8v). ...
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Can I die from touching one capacitor lead?
Suppose I have a charged capacitor and I only touch one of the plates or leads.
Will current start flowing through my body?
I think yes, because there is an electric field between one plate and Earth/...
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What would happen if I inject the charges (ESD) at PCB many times and PCB is completely floated (isolated) from the earth?
Just I wonder:
If I inject the charges (ESD) at PCB many times and PCB is completely floated (isolated) from the earth.
Will charges be dissipated or remain?
I think charges will be charged in the ...
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Vaneless ion wind generator: isn’t the maximum output theoretically limited?
I was thinking more specifically about the Dutch model of the kind EWICON : https://en.m.wikipedia.org/wiki/Vaneless_ion_wind_generator
Here is what puzzles me:
If the wind is strong enough to carry ...
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Soldering iron resistance reading
I’m learning about electrostatic discharge and I’ve read that my soldering iron should have a ‘grounded tip’ which I think means its power plug should have an earth prong which it does.
I took a ...
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Why capacitor 3 loses energy as it induces current in other capacitors
plate B of capacitor 1 and 2 are connected to capacitor 3 to provide potential difference. Part A includes capacitor plate and dielectric.
When part A and B are connected the positive charges will be ...
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What will be the steady state Charge distribution of given configuration- battery vs capacitor
I was try to figure it out what should be the charge distribution over the spherical conductor of radius R (in figure below) in following two configurations-
Assumptions
length of wire (l) connecting ...
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Ultra electrostatic capacitor generator
Part B of ultra capacitor 1 and 2 are connected to ultra capacitor 3 to provide potential difference.
Part B includes charge collector and electrode.
Part A of ultra capacitors 1 and 2 include the ...
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Generating current using capacitor
If you get a capacitor that is two plates and a dielectric and next to it you put two plates close but not in contact at opposite sides and the capacitor in the middle is charged, each of its plates ...
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Can a multi meter measure a potential static discharge?
Can a multi meter measure a potential static discharge like between hands and laptop before I open cover and replace a battery? Like if I touch laptop and my hands with the each two probes of a multi ...
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Electrical work sign convention
If I understood the correct sign convention it's as shown in the below sketch
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Trying to make an electrostatic battery charger
Can the DC layout charge a battery? I see as if it is in a solar cell format. I know that for a solar cell, when light hits the cell an electron is discharged but the semi conductor only lets it go in ...
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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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USB digital microscope and ESD safety (maybe power supply problem)
I have an ESD mat, ESD wrist strap and a Chinese USB (power only) digital microscope(Andonstar ADSM201.)
I use the microscope for soldering and inspection at home for hobby projects.
The microscope ...
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Using method of image to find surface charge density
Two point charges of 50nC and -20nC are located at (-3,2,4) and (1,0,5) above the conducting ground plane z=2. Calculate: a)The surface charge density at (7,-2,2), b)\$\vec D\$ at (1,1,1)
Now, ...
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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 check for the ESD protection of the capacitors
I have this circuit
I need to check whether my input capacitors C0001-c0004 are protected for ESD events.
My ESD pulse spec: +/-8kV, 2kohms & 330pF. I have taken 130% of this +8kV as my ESD pulse ...
user220456
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Electrostatic Discharge on new Workbench Setup
I'm setting up a table at home to do some electronics work (assembling microcomputer kits like the Maximite 2 and similar projects that require handling of sensitve IC chips).
I have a desktop lamp ...
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Calculating the unknown charge using the \$2\$ remaining charges in this arrangement
The overview of the problem and the solution and my thoughts are as below.
"/*" represents about my comment.
We'll handle the \$3\$ point charges in the vacuum.
Firstly the \$2\$ charges are ...
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Imagining electric flux intuitively
I know that electric field doesn't really flow, so whenever I'm trying to imagine electric flux like an amount of water passing through a window intuitively, I can't relate these two things.
Can ...
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Can an electrostatic motor produce constant torque at varied speed?
The idea of this question came from a DC motor that produces less torque by greater speed.
Can an electrostatic motor produce constant torque at varied speed?
How can I make a mathematic model of ...
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How it is determined whether an equal sign can be used within the boundaries?
Why equal signs weren't used for limits(r < a, a < r < b, r > b instead of r <= a, a <= r <= b, r >= b)?
Two concentric spherical surfaces of radius a and b = 2a are in vacuum ...
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Can an electrostatic voltage be divided with very large resistors?
Is it possible to divide an electrostatic voltage from a Van de Graff generator or electrostatic generator with very large resistors?
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Charge transfer in conductors of different metals by touching
when we touch two metallic conductors one is neutral and other has excess of charges,
Case 1- Both metals are of copper, then we can calculate actual charges on them at steady state by capacitance ...
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Static Electricity - and charges
When we comb our hair (with a plastic comb) and then bring the comb close to bits of paper, the bits get attracted to the comb. I understand this is because the comb is now electrically charged.
Why ...
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Voltage boosting device for electrostatic experiment
I want to get 2kV to 6kV (adjustable) for performing electrostatic experiments with parallel plates.
What device can produce such high voltages from the 230V mains?
I watched a video on YouTube ...
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Electrostatic protection - input and output ESD protection added to op amp w/built-in ESD
I have an op amp circuit using the OPA2626 that has a built-in input/output ESD protection of +/-3000V human body model. The circuit is 3.3V single supply, non-inverting, with only an external ...
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