Questions tagged [electric-circuits]
An electronic system, with closed loop current flow, and relative electrical potentials present across electrical components.
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Are the plates of a battery really charged?
In a zinc/copper Daniell cell correct me if I am wrong :
Zinc has 2 valence electrons. So it wants to get rid of them. To do so it sends them to the copper which needs 2 to complete its valence shell....
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Why does connecting a battery's positive terminal to the negative terminal of another battery not create a short circuit?
This is a question regarding the physics behind the observation.
I have guessed the answer to the question, but I may be wrong, so I want to wait for the responses before posting it.
Some major ...
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Does a Mobius resistor have zero inductance? How would you calculate the inductance?
Wikipedia describes a Möbius resistor as follows, and the Patent for this device gives a similar description.
A Möbius resistor is an electrical component made up of two conductive surfaces separated ...
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Why does a Resistor cause a potential drop?
I need to know the underlying physics of what exactly happens different with the electric field in the resistor than in superconducting wires.
Why is it that when I connect a resistor, potential drops ...
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What is Electromotive force (EMF)? How is it related to potential difference?
What is Electromotive force (EMF)? How is it related to the potential difference? Is it created by the potential difference in any conductor? Is it a process? Why is it called force?
Does writing EMF ...
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Is current in superconductors infinite? If they have 0 resistance then I (V/R) should be infinite? [duplicate]
I learned many years ago that according to Ohm's law, current is equal to voltage divided by resistance. Now if superconductors have zero resistance then the current should be infinite.
Moreover the ...
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How can I put a permanent current into a superconducting loop?
I know that you can use induction to create a current in a superconducting loop, but this only works as long as the coil that induces the field has a current flowing through it. And obviously, this ...
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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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Why is current the same in a series circuit?
So I am a 10th grade student and my teacher told me that the current is the same at every point in a series circuit. It does split up in parallel circuit but it then recombines and the current flowing ...
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Reduction of Maxwell's equations to classical circuit theory
Can classical circuit theory based on lumped element models be obtained from Maxwell's equations as a limiting case in an appropriate sense?
If this is the case, what exactly are all the assumptions ...
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Why does current density have a direction and not current?
Current is a scalar $I$ with units of $\mathrm{[J/s]}$. It is defined as $I=\frac{\mathrm{d}Q}{\mathrm{d}t}$.
Current density is a vector $\vec{J}$ (with magnitude $J$) with units of $\mathrm{[J/s/m^2]...
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What is the physical explanation for energy transport in simple electrical circuits?
Keeping it simple, what is the physics approach to a current in a wire connected to a battery? How does the electric field behave?
I've read somewhere that, contrary to the common conception, ...
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How do you determine power flow direction in a transmission line?
Below is a picture of a typical transmission line(about 200 kV). Is there a simple physics experiment which can be performed safely near the line, to determine the power flow direction. Or in other ...
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Why is the return current through a printed circuit board's ground plane concentrated below the circuit trace?
The Wikipedia article on ground plane says
In addition, a ground plane under printed circuit traces [the paths that the circuit currents take] can reduce crosstalk between adjacent traces. When two ...
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What happens if you use a battery to charge up a capacitor fully, and then disconnect the battery, where does the charge 'go'?
The title says it all really, but I think that since the battery is disconnected there is now an 'open circuit'. I know that charge can only flow if the circuit is complete (closed).
But the part that ...
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