Questions tagged [capacitance]
The ability of an object to store electric charge.
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Express Laplace transform of voltage across a capacitor in terms of charge
In Charge Tunneling Rates in Ultrasmall Junctions section 2.1, the authors consider the problem of charge relaxation in a simple circuit shown in Figure A.
The implicitly use an assumption made about ...
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Current through points with no voltage drop
I've had a problem with switches in between parallel circuits.
In this textbook question:
The answers state "Note that there is no voltage drop across the voltmeter". However, there is a ...
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Predicting voltages in RLC series circuits from AC source: differences in order?
Hoping this isn't too homework-like, but I'm missing some sort of concept here. Doing a lab, and I have to use previous data to predict the voltage across the 2nd and 3rd elements (e.g. order is LCR, ...
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How does earthing a plate of an isolated charged capacitor even work?
If one plate of an isolated charged parallel plate capacitor is earthed, then that plate must have a potential zero after being earthed as that is what earthing an isolated conductor does, but ...
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A capacitor partially filled with dielectric [closed]
Assume a parallel plate capacitor that was charged up to $Q_0$ from a source $U_0$ and then disconnected from the voltage source. The plates have an area $A$ and the distance between the plates is $d$....
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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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Energy in Dielectric Medium as a Sea of Dipoles
Simply, why is the energy density in a dielectric medium = $\frac{1}{2}K\epsilon_oE^2$ where K is the dielectric constant of the dielectric medium?
Working proof
Consider a capacitor that is charged ...
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Parallel plate capacitors with dielectrics [closed]
I was studying capacitors with dielectrics ,where my teacher gave one example for us to solve
between the parallel plate capacitor there is dielectric which is further divided into four dielectrics ,...
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Resistor Capacitor circuits
I am a high school physics teacher and came across some issues today that I am unable to explain.
We made a circuit with an $11$ V power source connected to a $100~k\Omega$ resistor and $100~\mu F$ ...
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Charging a capacitor without closing a circuit
It might sound absurd but is it possible to charge a capacitor solely by connecting the positive terminal of a battery to one plate of the capacitor and the negative terminal of another identical ...
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Trick question: why do dielectrics and isolated conductors affect capacitance differently?
This question confused me a bit, but I figured out the answer. I just want to share this trick question here.
Trick question: Dielectric material produces net surface charge when placed in electric ...
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Self- and mutual capacitance
Consider having a positively charged plate with charge $+Q$ and potential at surface $+V$. Then, its self capacitance equals $Q/V$. Now, i have a similar plate with charge $-Q$ and potential $-V$. The ...
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Electric field at a point due to dielectric inserted in between a parallel plate capacitor [closed]
Here, I have a parallel plate capacitor with each plate having surface charge density $\sigma$. A dielectric of dielectric constant $K$, is inserted partially between the two plates. What would be the ...
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Repulsive force from charge accumulation in a capacitor plate?
During a charged state of a capacitor (Regardless of the type of capacitor),
Simple parallel plate:
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Parallel plate with dielectric material in the gap:
]3
Supercapacitor:
How is the ...
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Capacitance of a dielectric capacitor with two sphere electrodes instead of parallel plates
EDIT: title changed to be more descriptive.
I would like to calculate the capacitance of a material (in plate form with thickness d and a known permittivity $\varepsilon_r$ ) between two sphere ...
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