Questions tagged [phasor]

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Does an oscilloscope subtract voltages as phasors?

I want to measure two voltages on an oscilloscope. They are not in phase. I want to know the magnitude of the voltage difference. The oscilloscope has an in-build math function to subtract the ...
28 views

Superposition theorem with phasors [duplicate]

Can someone explain the superposition theorem step by step when applied with phasors (AC circuits)? I think books and websites mostly include examples of how to solve something with superposition but ...
48 views

Complex Amplitudes and Exp'l Increase/Decrease

The following are quotes from a textbook, If S(t) is represented as a rotating phasor, the angular frequency of the phasor can be thought of as velocity at the end of the phasor. In particular ...
38 views

Phase voltage of a three-phase source with impedances knowing the line voltage

How can we determine the phase voltage of a balanced triangle three-phase source when impedances are present in that source and knowing the line voltage? When we only have voltage sources, the line ...
72 views

Is the frequency response of a circuit only valid for steady state (phasors)?

This is my first post. I just finished a course about advanced circuit analysis techniques (the content was taken from textbooks by Sadiku, Hayt and Irwin.) As you know, phasors are used to solve ...
79 views

Transformer's Primary and Secondary Voltages

In general, which is the phase relationship between the primary and secondary voltages of an ideal transformer? Does it depends on the dot convention?
72 views

Phasors and Fourier Transform

I have always been told that for a sinusoidal variable (for instance a voltage signal), the fourier transform coincides with the phasor definition, and this is the reason why the analysis of ...
42 views

AC signal analysis: Voltage dip (amplitude dip) at time = 0

I'm working on a series RLC problem where the input voltage is a sinusoidal function for all time. The catch is, for t < 0, the sinusoidal function is of greater magnitude than t >= 0. There is no ...
28 views

What is the DC component of the sum of phasors?

I am preparing for the written test conducted by IISc Bangalore for admission into their graduate program. I happened to come across a sample paper from 2016, I think. I am struggling to understand ...
124 views

How does one relate an RC circuit's time domain solution to phasors?

It seems to be a given for phasor analysis that the voltage across a capacitor can be defined as follows: $$V_{C}(t) = V_{A}\cos(\omega t + \phi)\tag{1}$$ Where Vc(t) is the capacitor's voltage at ...
89 views

Why can phasors be used simplify getting instantaneous power from instantaneous curent and voltage?

If instantanoeus power is p(t) and instantaneous voltage and current saying for a resistor are v(t) and i(t), then p(t)=i(t)*v(t). But if you convert v(t) and i(t) to their respective phasors and ...
74 views

Is my calculated capacitor sign correct?

I have the following circuit where I would like to obtain an analytic expressions for the value of $Cs$ and $Rs$ only kowning the phasors $\bar Vina$ and $\bar Vinb$ there displayed, I don't ...
143 views

Phasors: why is my book using sines?

When I learned phasors I learned we passed from sinusoidal to phasor this way: $$\sqrt{2} V\cos(\omega t+\phi) \rightarrow \sqrt{2} Ve^{j\phi}$$ However I'm now studying for a book that does this: \$...
69 views

Output of AC op amp circuit has unknown superimposed signal on top of expected output signal

I am trying to find the voltage gain of a certain ideal op amp circuit with a sinusoidal input. However, when I simulate the circuit, the output shown seems to be my calculated output but with a ...
40 views

Actual direction of phasor current - Power Calculation

I am trying to calculate the complex power in this circuit. I used nodal analysis to find Vc, and the voltage at the top of the 2H inductor (=3.13<177.8 V_RMS). I did the math for all elements in ...
114 views

Determine the power dissipated in W in the 5 Ω resistor [closed]

simulate this circuit – Schematic created using CircuitLab Excuse me for my really bad use of the schematic feature I just didn't know how to switch to the phasor domain. Anyway, I'm asked to ...
285 views

Phasor vs Vector vs Space Vector

I wonder what is the difference between a Phasor, a Vector and a Space Vector? A phasor is also a rotating vector in space then it means that a space vector is same as a phasor? Also by definition a ...
59 views

163 views

Intuitive meaning of setting determinant = 0 in oscillator analysis

I'm reading a book on oscillators at the moment and the author is explaining a method of analysis based on the system determinant. Given the following generic FET tuned oscillator arrangement: and ...
97 views

constant independent of time, meaning of this line?

can someone please explain last paragraph in the Picture that i have uploaded, in layman's term specially this phrase "constant independent of time"
57 views

Clarification needed regarding average power through a load

The question for the following circuit was to find the average power through the load $Z_{L}$. The first and second image shows that $I_{2}$ and $V_{2}$ were found. I assumed that the ...
283 views

Reference phasor(or quantity)

So I learnt about phasors and phasor representation this week in college. I noticed that in every example problem that we did, one phasor was chosen as reference and the angle was taken as 0°. My ...
78 views

Other than Voltage, Current and Power, what else can a Phasor describe?

I've always thought of just these 3 things that a Phasor can describe -- the magnitude and phase of the sine function of these 3, vertically centered at 0 and of the same frequency. Are there more?
55 views

Nodal Analysis of Circuit

Given this circuit, we want to find V(t) or the equivalent D node circled. I set up the nodal analysis equations in the phasor domain as follows, with a super node at the dependent source. However,...
78 views

Phasor with source

220 muF stands for $220\cdot10^{-6} F$. Sorry for putting it that way. The question is to find the equivalent impedance Z with a frequency = 50 Hz. I know how to find all the Z of the capacitor and ...
234 views

Finding voltage across an RL circuit

Given the following circuit diagram I know that in order to find either values, I can apply... or ... But I am having some trouble understanding how I can get rid of the imaginary term j in ...
54 views

Modelling a power supply system

I understand that for a RL based circuit connected to an AC supply, the impedance for the inductor is jωL and also I need to find the net resistance of the load model which I have derived to be (R*jωL)...