Questions tagged [circuit-theory]
The circuit-theory tag has no usage guidance.
127 questions
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Meaning of Sigma in Laplace transform
I found the question below in a forum and I also have same problem. Unfortunately, there is no answer at all so I will post it here hope someone could make it clear.
A gain relation in a circuit of ...
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Flow of electricity. Need explanation [closed]
simulate this circuit – Schematic created using CircuitLab
People are taught how to calculate this very simple thing, and the calculation goes from source plus to minus, and the diode is there ...
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What is the current - voltage relation in a wire?
This is a question from a TV game show. Fill the blank with appropriate words.
Current flowing through a wire is ... to the voltage drop across the
wire.
The answer in the dots is "proportional"....
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Network theorem origin
While finding the norton's equivalent curcuit,we
1.find the short circuit current through the load
2.Find the resistance between the two points across which load is connected shorting the voltage ...
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What hypothesis are needed to support the following argument on a three phase system?
Given the following three-phase system:
simulate this circuit – Schematic created using CircuitLab
Suppose to set 2 wattmeters as follows:
\$P_{21}\$ which measures current \$I_2\$ and ...
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Am I insane to question that only with a closed path can electrons move?
First of all let me just state that I do not feel confident enough to tell anyone anything about how electric circuits work or anything about the physics behind them because I simply do not know or ...
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Discharging Circuit with LED indicators?
I'd like to create discharging circuit with four LEDs indicating how much charge is left from the discharging battery. It needs to be a low cost solution (no Arduinos; only simple circuit components) ...
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What does this circuit show?
I am just starting out looking at more complex circuit diagrams, and I really do not understand what is being shown here
My initial guess was that this was a series circuit with the probe (consisting ...
CommunityBot
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Basic circuit with diodes analysis
I have the following circuit:
How to determine the waveform of Vout, maximum values for positive and negative half-period segments, and the average value of Vout?
Input voltage Vin has a sinusoidal ...
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2
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First order circuit with t=0+ , t=0-?
Yesterday I tried to solve a question in a second order circuit , but I couldn't ! because I have problem understanding the concept of 0+ , 0- !
So let me try it in a first order circuit , it ...
CommunityBot
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Equivalent resistances with the superposition theorem
I have the following definition and explanation of the superposition theorem. I don't understand how the resistance values are calculated. I understand that \$R=V/I\$, so \$I=V/R\$. But how is the ...
Null♦
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Equivalent Current in Circuit
I have the following circuit:
I'm trying to calculate the equivalent current. In my approach resistors 2 and 1 are in parallel so their equivalent resistance would be 2/3 then since resistors 1 and ...
Null♦
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Adding a delay to a door alarm?
Hi guys I saw these window/door alarms https://m.dollartree.com/h5/r/product/Battery-Powered-Window-Alerts/p328789/index.pro at the dollar tree that work off a reed switch. When the magnet bar is ...
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Is voltage and current sources linear or nonlinear?
From the circuit theory it is known that an element whose response is linear is called linear element such as resistor, capacitor. For example, in case of resistor the slope between V and I is a ...
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Finding some variables in a second-order circuit?
Can any one please help me solving these questions .. I always get a wrong answers :/
The first order circuit is much easier than this one !!
This is my answer :
for the first time i thought it ...
CommunityBot
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capacitive proximity sensor - how does it work
I know 3d printers such as the i3 use a Capacitive proximity sensor to try compensate for the uneven surface of the print bed. for example this one seems to be popular
https://www.amazon.co.uk/gp/...
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CMRR for an ideal op amp
In the question, he told me from the begging that it is an ideal op amp .. so A(cm) =0 !!
How can I find the CMRR then !!
I tried to analyze the circuit to be sure!! And i got the same !
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Why is the current in this circuit 100mA?
I am just learning electronics and trying to reason some figures I measure in simple circuits.
I need a bit of a hand with this one.
I have a 3.2V power source, and 2, 1 ohm resistors wired in ...
CommunityBot
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RL circuit Step-Response Equation explaination
Im having difficulty understanding the integral calculation in number 4. How does (Response) section of "V/L" convert into "V/R"? Where does exponents go?
The last equation is from the textbook.
*I ...
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Mismatched transmission line at DC
The characteristic impedance equation in transmission line theory is this:
$$Z_0 = \sqrt {\frac{R+j\omega L}{G+j\omega C}}$$
Take the case of a twisted pair transmission line, say the cat6 cable ...
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What's wrong with parallel conductors?
Regarding AC systems (like for homes and such), a circular path is called a parallel conductor. It's illegal (according to the NEC section 310) except under certain circumstances. But I have noticed ...
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Since, resistance is a passive element, so why its value comes out to be negative?
In thevenin's theorm,
In a circuit with current dependent current source (value=2i, pointing downwards), in parallel with 2 resistors in parallel i.e 2ohm and 4ohm. And current "i" in 2ohm resistor ...
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What damage can 1500V cause to a circuit? [closed]
I'm working on a device that has a supply of 220 V. The output has an LED at the end of a fibre-optic cable coming from the device in question.
If, for some reason, a tremendous amount of voltage ...
- 315k
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voltage in an electrical circuit consisting of a current source
In the following circuit is it correct to ignore the current and simply add all the voltages to measure voltage at open end?
simulate this circuit – Schematic created using CircuitLab
If it is ...
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Finding CutSet Matrix from a Circuit
I have the following question
My answers are
Please let me know if my approach and answer is correct to find the Cut Set Matrix.
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Current Division Rule
I have the following circuit.They are simplifying the circuit and applying
current division
To use current division the incoming current should not have a resistor in between,right?
But in this ...
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Disambiguation of AC Analysis and Small Signal Analysis
I am trying to understand Small Signal Analysis (SSA) for Diodes and BJT transistors through different textbooks but I have some issues.
Is AC Analysis the same as SSA? I have seen hints that imply ...
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