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 exactly do charged capacitors decrease current?
I recently learned about how capacitors function in electric circuits, and I came across an apparent contradiction that I wanted to ask about. On one hand, I know that as charge builds up on the ...
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Resistance in electric circuit [closed]
How do resistor restrict the flow of electric current? been trying to understand this and still haven't gotten any conclusive answers yet.
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How do I determine the correct $R$ for $RLC$ low pass filter? [closed]
I am trying to build a $RLC$ low pass filter that atenuates the frequency below 4500 Hz. However, I have encountered some problem when choosing the correct $R$ to work with.
Here is the Circuit
Here ...
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Potential difference across a bulb
I came across this question in DC Pandey Electricity and Magnetism:
Image transcript:
An electric lamp which runs at 100 V DC and consumes 10 A current is connected to AC mains at 150 V, 50 Hz cycles ...
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Could anyone help me with this high school physics problem regarding circuits and current? [duplicate]
Three identical resistors of 6 ohms are arranged as shown in the diagram. What is the resistance between X and Y?
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Parallel resistors not sharing the same nodes?
In the below circuit the switch is closed at $t=0$. I understand the calculations regarding the initial and final voltages across the capacitor. But in order to calculate the resistance, he says that ...
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Coolidge tube circuit doubt
Consider a typical Coolidge-class X-Ray tube. The filament (cathode) is part of two circuits: the filament circuit, which heats up the filament by passing current through it to enable thermionic ...
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Irrational numbers from finitely many resistors
Given a rational number $p/q$ and a handful of unit resistors (resistors with resistance $1$ $\Omega$ each), we can naively put $q$ resistors in parallel to get an effective resistance of $1/q$, and ...
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Current distribution in a conductor of uneven conductivity. Calculation of effective resistance of such a conductor
Imagine a slab of 3x3 conductor, in which the center piece is of higher conductivity. What is the current distribution $\vec{J}(x,y)$ like? How about the electric field?
I can think of two laws ...
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Why is mass mapped to inductance in the Mass-Spring-Damper ↔ $LCR$ analogy?
In the Mass–Spring–Damper ↔ RLC Circuit analogies, mass is mapped with inductance.
F=mdv/dt, V=LdI/dt
From a cause–effect point of view, I find this confusing:
In mechanics, a force causes ...
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Does the time change in an induced magnetic field produce an electric field?
This question slightly differs from my previous question. I argued with a friend of mine regarding whether a moving current-carrying wire has an additional electric field with an origin other than the ...
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How can this laptop charging work, or not work? [closed]
This question start from a meme. However, when I tried to understand whether this is viable or not, I highly doubt it's even possible to charge using VGA port, because it's part of different circuit, ...
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Can ammeters detect displacement current?
I have found a related question to the one that I ask below here, but it doesn't quite directly answer my question.
Apparently ammeters sometimes (or always?) measure current by measuring magnetic ...
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Kirchhoff's voltage law in Inductor Circuits [duplicate]
Kirchhoff's voltage law is based on conservative field whereas the induced field developed in an inductor is non conservative so how do we use kirchhoff's voltage law in a loop with one of the ...
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How exactly does a capacitor smooth voltage in a AC-to-DC rectifier?
hello, i have just started learning about capacitors and I wanted to clarify my understanding of how exactly a capacitor works to 'smooth voltage' in an AC rectifier circuit, as shown in the diagram.
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