The capacitance tag has no wiki summary.
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Charge on capacitor plates in series combination?
Suppose 2 capacitors are connected in series, the plates connected to the battery terminals receive charges $+q$ and $-q$, and the isolated plates in the combination receive equal and opposite charges ...
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1answer
52 views
Unrolling electrolytic capacitors
If I take an electrolytic capacitor, remove the aluminium casing, unroll the foil/ electrolyte-soaked paper, if charged, will it still work? And what if I took of the cathode foil and wrapped the ...
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1answer
96 views
Will I recieve a shock if I charged a capacitor then i touch the 2 poles in same time?
What happens if I charged a capacitor then i touch the 2 poles in same time?
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1answer
310 views
how to calculate electric relative permittivity of fluid or medium
I am confusing in calculating permittivity of the fluid. Permittivity differs from one fluid to another.
$$\varepsilon=\varepsilon_r\varepsilon_0$$
Since it is an electrical property combined with ...
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1answer
46 views
Can we transfer the charge on a plate of a capacitor elsewhere?
I know it is hard , but can we transfer the charge on a capacitor plate elsewhere?
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111 views
Charging a metal plate
I am supposed to find a way to charge a metal plate with a defined charge ( in nanocoulomb) and it must have a + charge so basically i want to know if this way is correct and applicable, and if there ...
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1answer
46 views
Charge of an electrolytic capacitors
I can't understand the electrolytic capacitors, when a capacitor has a capacitance of 100 microfarads, does that mean that when it is charged with 100 volts will the charge of the plate be 0.01 ...
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2answers
405 views
Poynting vector of a wire between capacitors
A capacitor made of two circular plates of radius $L$ separated by $d$, initially the plates carry $\pm$ Q charge.
Then a wire of resistance R is placed between them, how do I go about deriving a ...
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3answers
330 views
Find Inductance in a Coil
Question: An inductive coil has an internal resistance of 20 $\Omega$. When an AC Voltage source with a frequency of 100 Hz is connected to the coil, the current lags the voltage by 30 degrees. What ...
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1answer
107 views
Will the plates of a parallel plates capacitor keep its charge after being charged then seperated from the non- conductor?
If i had 3 plates 2 metals and 1 glass .I put them together to form a basic parallel plates capacitor.
After charging it and approaching it to an electroscope nothing happened that's because ...
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2answers
150 views
Effect of charges near a parallel plate capacitor
If I charged a parallel plate capacitor. And then, I insert a charged body near one of the plates.
Will there be any interactions like attraction or repulsion?
What if I disconnected the battery?
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0answers
222 views
Capacitance of this unusual capacitor
This capacitor is composed of two half spherical shelled conductors both with radius $r$. There is a very small space between the two parts seeing to that no charge will exchange between them.
...
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1answer
165 views
Why is water not used as a dielectric in the condenser?
The dielectric constant of water is very high. Then why is it not used as a dielectric in the condenser?
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2answers
147 views
Energy in electric field
I'm having some trouble understanding a homework question and would appreciate some help.
The question is as follows:
Jenny charges a capacitor with the help of a battery. She then removes
the ...
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3answers
238 views
Change in attraction of charged bodies
If I insert a piece of glass between two objects carrying different charges, would they still attract?
If they attract, does the piece of glass affect the force of attraction and is there any formula ...
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1answer
225 views
Breakdown voltage of a dielectric
I know that a capacitor with a dielectric can operate normally up till a certain voltage (AFAIK called breakdown voltage) which depends on the strength of the dielectric placed between the plates. ...
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3answers
229 views
A problem of missing energy when charging a second capacitor
A capacitor is charged. It is then connected to an identical uncharged capacitor using superconducting wires. Each capacitor has 1/2 the charge as the original, so 1/4 the energy - so we only have 1/2 ...
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4answers
551 views
Is there a deep reason why springs combine like capacitors?
I was solving a practice Physics GRE and there was a question about springs connected in series and parallel. I was too lazy to derive the way the spring constants add in each case. But I knew how ...
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0answers
227 views
Calculating capacitance of integral PCB components
I posted this question originally with Electrical Engineering Stack Exchange but nobody seems to know the answer. So I thought a physicist might find the question more approachable.
Formulas for ...
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2answers
277 views
Proof of charge existence on a grounded conductor
A question regarding the existence of charge on grounded conductors is confusing me.
Could there be charge on a grounded conductor?
How does this not contradict Gauss's Law?
Since every conductor ...
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0answers
71 views
Charge Based Capacitance Measurement (CBCM)
I am using Keithley 4200-SCS to measure the device capacitance.In order to get total capacitance of the device, the Gate terminal is voltage biased and the other three terminals are grounded.
I wanted ...
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3answers
455 views
When I connect two charged capacitors side by side, what will be the voltage across them?
Say, I have two charged capacitors, one 3mF and one 2mF. The voltage across them are 20V and 30V respectively. Now if I connect the two capacitors side by side as shown below, what will be the voltage ...
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4answers
2k views
Will a charged capacitor discharge if one lead is connected to ground?
If I charge a capacitor and connect one lead to ground keeping the other lead floating, will the capacitor discharge ?
...
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3answers
1k views
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4answers
294 views
Why does it seem that the potential difference dependence of capacitance and total energy stored in a parallel-plate capacitor are contradictory?
Consider a parallel-plate capacitor. Charge is stored physically on electrodes ("plates") which are flat and parallel to one another. If one electrode has charge $+Q$ and the other electrode has ...
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2answers
347 views
Parallel-plate capacitor
I'm trying to grasp parallel-plate capacitors in a class of electromagnetic field theory. My book leaves out a lot and I couldn't figure it out from what I found on Google.
The book's procedure is ...
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5answers
3k views
What is the difference between a battery and a charged capacitor?
What is the difference between a battery and a charged capacitor?
I can see lot of similarities between capacitor and battery. In both these charges are separated and When not connected in a circuit ...
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3answers
427 views
Parallel or series connection?
Are C1, C2 and C3 connected in parallel, or C2, C3 in parallel and C1 in series with C23?
Btw it appeared as a question in the basic physics Albanian A-levels yesterday. You had to find the ...
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2answers
68 views
Permitivity $\mathcal{E}$ as a function of Voltage across a medium
What I wanted to Know was is there a change in Dielectric Permitivity constant as the voltage increases.
My question arose from the fact that for a breakdown voltage to be reached the Permitivity ...
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3answers
550 views
Distorted colors of Google StreetView photographs near electric power lines
This is a followup to my question:
Cyclist's electrical tingling under power lines
Some users presented a convincing picture that the electric shocks under power lines are primarily from the ...
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3answers
3k views
How is calculated the potential between two capacitors in series?
Suppose to have two capacitors in series:
The voltage in the middle point will be:
$$
V_X = V_1 \frac{C_1}{C_1+C_2}
$$
How can this be explained? It's been asked in electronics, and explained in ...
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2answers
514 views
Charge distribution on a plate of Capacitor with Dielectrics .
I had this Homework Problem with a capacitor (parallel plate) that has a group of 3 dielectrics between it like so :
Now We were asked to find the equivalent capacitance and the distance of ...
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2answers
1k views
RC circuit theory and voltage in the capacitor vs Ohm's Law
Consider a simple series RC circuit at steady state (capacitor is full).
I've been told that once the capacitor is full we can literally "cut" the circuit because no current can flow.
That ...
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1answer
258 views
Dielectric in a parallel plate capacitor
Uniform charge: each atom has charge $q$.
Magnitude of dipole moment is $q s$, where $s$ is the distance the nucleus is shifted.
According to my notes, the charge on the surface of a dielectric in ...
0
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1answer
205 views
Why is this charge distribution in correct? Capacitors in parallel and series
Please consider the circuit diagram below, in particular, look at the capacitors enclosed by the green loop.
*Note that the green loop and the (+) and (-) charges on the plates were drawn by me, ...
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3answers
204 views
What's the right way to calculate charge on a capacitor?
How much charge is on each plate of a 4.00-F capacitor
when it is connected to a 12.0-V battery?
I said 2.4 x 10^-5 C because there are two plates of a parallel plate capacitor. But the key said only ...
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2answers
327 views
Capacitors in series
I need some explanations on the green underlined sentences.
1) "Must continue to have zero net charge..." What if the $\ C_2$ had +2Q on the left plate and -Q its right plate? The net charge ...
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1answer
308 views
Potential difference between conductors
Reading some books there is something that i don't understand. Is the capacitors topics when they name a potential difference between conductors.
As i know, Potential difference is the difference in ...
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2answers
118 views
Is it true that capacitors closer to a power source charges quicker and gets priority?
Let's say I hook two capacitor in a parallel circuit with a voltage source. Would the capacitor closer to the battery be charged up first? Because when the voltage excites and draws electrons from the ...
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3answers
330 views
Is this really how a capacitor works? Why doesn't it behave like a resistor?
My book says a capacitor is two conducts being connected by an insulator. Now let's take a parallel plate capacitor to simplify the problem I have.
Suppose I got two parallel plate capacitor in ...
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1answer
237 views
Calculating capacitance of arbitrary plate shape and arrangement.
Looking for suggestions on how to approach calculating the capacitance of a capacitor where the plates have an arbitrary shape. I've seen derivations of capacitance for a few highly symmetric ...
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3answers
458 views
Why do charges enter the capacitor in the first place?
I have been studying Capacitors for the past year now and the one thing I don't understand is how a charge is stored on the capacitor. Essentially, a circuit with a capacitor is an incomplete circuit ...
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3answers
805 views
Charge Distribution on a Parallel Plate Capacitor
If a parallel plate capacitor is formed by placing two infinite grounded conducting sheets, one at potential $V_1$ and another at $V_2$, a distance $d$ away from each other, then the charge on either ...
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1answer
873 views
RC Circuit , Calculate Time Constant
Given this diagram:
With S1 switch closed and S2 switch left open, I am trying to find the time constant
Relevant equations
I know τ = RC for a basic circuit, but how would you calculate it for a ...
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0answers
262 views
What is a boundary condition for capacitors/dielectrics?
I am extremely confused about what boundary conditions are. One minute ago I was solving easy capacitor questions and the next minute I am being asked boundary condition questions and there is no such ...
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0answers
219 views
Dielectric in Parallel Plate Capacitor
Given a parallel plate capacitor of width $w$, length $l$, with a dielectric moving along the length $l$. Let the dielectric be from $x$ onwards.
The capacitance will be $\frac{w \epsilon_0}{d} ...
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1answer
979 views
How to calculate the charge and the potential across a charged capacitor charging an uncharged capacitor?
Initially, there is a single capacitor $A$ attached to a power source that charges it to a certain voltage $V$. Once it is charged, it is instantaneously removed and placed in a circuit with an ...
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1answer
340 views
How do home-made capacitator bottles affect a tesla coil?
In the tutorial I'm following, the guy uses 6 snapple bottles to make capaciter (by covering them with foil and filling them with salt water) for a 9kV 30mA input. I have a stronger transformer (15kV ...
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1answer
424 views
How is capacitance defined for three concentric spheres?
If we have a configuration of metal concentric spheres (each of negligible thickness) of radii $r_1,r_2,r_3$ respectively and $r_1<r_2<r_3$, and we are given the potentials of the spheres to be ...
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3answers
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Electric field at a point inside a capacitor
Let's say I have a parallel plate capacitor.
How would I find the electric field at a certain point INSIDE the capacitor (inside the dielectric let's say). From what I understand, the flux of the ...
