Questions tagged [electric-circuits]
An electronic system, with closed loop current flow, and relative electrical potentials present across electrical components.
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How does energy flow in a circuit? Which is correct?
I have been very interested in this question since reading Electricity Misconceptions by K-6
There are two perspectives I have come across for how energy flows in a circuit:
Electrons carry charge. ...
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What is the most appropriate mathematical theory for electrical circuits?
What exactly are electrical circuits as mathematical objects?
It seems quite intuitive to me, that they are geometric realization of some graph with some additional structure.
Another thing I notice ...
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Could someone intuitively explain to me Ohm's law?
Could someone intuitively explain to me Ohm's law?
I understand what voltage is and how it is the electric potential energy and that it is the integral of the electric field strength etc. I also ...
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Is every open circuit a capacitor?
I think that even open-ended wires can let AC current flow through them, just with a low capacitance. I also think an antenna could be a capacitor and open ended. Am I thinking correctly?
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Electricity takes the path of least resistance?
Electricity takes the path of least resistance!
Is this statement correct?
If so, why is it the case? If there are two paths available, and one, for example, has a resistor, why would the current ...
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Is there a simple proof that Kirchhoff's circuit laws always provide an exactly complete set of equations?
Suppose I have a complicated electric circuit which is composed exclusively of resistors and voltage and current sources, wired up together in a complicated way. The standard way to solve the circuit (...
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Why is there an electric field in a wire even though it is a conductor?
If you take a perfect conductor, there cannot be a field across it since if there were, the particles would arrange themselves in a way to cancel out the field right?
Yet, why does the same not hold ...
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Why don't superconductors, which have zero electrical resistance, violate the second law of thermodynamics?
There are bunch of questions on here asking whether superconductors really have exactly zero resistance and answers saying they do. My question is how this doesn't violate the second law of ...
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How does power consumption vary with the processor frequency in a typical computer? [closed]
I am looking for an estimate on the relationship between the rate of increase of power usage as the frequency of the processor is increased.
Any references to findings on this would be helpful.
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Resistance between any 2 nodes on an infinite square grid
This question is motivated by this xkcd comic strip
.
The problem is indeed interesting, and my first recollection upon reading this was a similar problem in the book Problems in General Physics by I....
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Are voltages discrete when we zoom in enough?
Voltages are often thought of as continuous physical quantities.
I was wondering whether by zooming in a lot, they are discrete.
I feel like the answer to the above question is yes as voltages in the ...
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What's the physical meaning of the imaginary component of impedance?
As you know, impedance is defined as a complex number.
Ideal capacitors:
$$
\frac {1} {j \omega C} \hspace{0.5 pc} \mathrm{or} \hspace{0.5 pc} \frac {1} {sC}
$$
Ideal inductors:
$$
j \omega L \...
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Why is capacitance defined as charge divided by voltage?
I understand that capacitance is the ability of a body to store an electrical charge and the formula is $C=\frac{Q}{V}$. What I don't understand, however, is why it is defined as coulomb per volt. Of ...
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What happens to half of the energy in a circuit with a capacitor?
For a simple circuit with a battery supplying a voltage $V$ to a capacitor, let us assume that the charge on the capacitor is $Q$. Now, the work done by the battery or the energy supplied is given by ...
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What happens when we connect a metal wire between the 2 poles of a battery?
As I remembered, at the 2 poles of a battery, positive or negative electric charges are gathered. So there'll be electric field existing inside the battery. This filed is neutralized by the chemical ...
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