Circuit analysis Definition and 558 Threads

Summary: Perform nodal analysis on a circuit to find voltages. For a laboratory I am trying to find the nodal voltages for a circuit we built using hand calculations. I have the answer as we ran the simulation which shows all the nodal voltages, however my nodal analysis seems to be wrong as I...

Hi all, I tried to solve this, but I can't find the R(equal). I use the following method. The circuit: For t<0 the switch is closed so the iL(0-)=4 A For t>0 it opens and the iL(∞)=0 A Now, I want to find the value τ=L/R(equal) Then I will use the: iL(t) = iL(∞) + ( iL(0-) - iL(∞) )* (...

This is the circuit: I try with KVL: But the given answer is 6.66L33.67 Volts. So, I'm confused, any suggestions ?

I'm asked to solve for Vo for this equation. I've set the bottom node to be my reference node before applying nodal analysis. When included in the KCL equation for node at Vb, will the dependent voltage source 20iΔ be negative since the current through that element is leaving node C? Say, the...

Problem Statement: ) A circuit is constructed with six resistors and two ideal batteries as shown. The battery emfs are ε1 = 18 V and ε2 = 12 V. The values for the resistors are: R1 = R5 = 55 Ω, R2 = R6 = 110 Ω, R3 = 44 Ω, and R4 = 117 Ω. The chosen positive directions for the currents are...

Here is the question, and my solution is for question (a) : knowns : I = 12 cos 2000t = 12 ∠0° L=0.2 H R=200Ω ω=2000, XL = j*0.2*2000 = j400Ω Zt = (j400*200)/(200+j400) = 178.9 ∠26.57°Ω i want to find the power absorbed by R, so : IR = (Zt /R)*I = (178.9 ∠26.57°Ω/200)*12 ∠0° = 10.73∠26.57°A...

I already did part a and got the correct answer of 4.8 microC. However, I am unsure how to approach part b, where the switch is closed and apparently the two capacitors end up with different charges. For part b, since there is a path between the two capacitors, I don't know if I am able to...

That is, for Supernode -1,3 (12V branch) , we do Nodal Analysis and we have (V2-V3)/2 , over the 2 ohm branch. But this current is not included in the Equation 1 in the solution I have attached(Which is my only source to cross check answers/solution right now.) Is the solution wrong? Thanks...

From what I understand is that you can sum up R3 and R4 to get 350 ohms Then you can can a parallel circuit with the missing resistors, 4amp and the new 350 ohm resistor and that's about it. My textbook says the answer is 55 ohms for the resistors and the current is 0.073 but I got 3.75 ohms...

Summary: Looking for guidance on how to model an RLC circuit with a system of ODES, where the variables are the resistor and inductor voltages. This is a maths problem I have to complete for homework. The problem is trying to prove that the attached circuit diagram can be modeled using the...

Above is the figure of the question. According to Kirchhoff's Rule, I have obtained three equations $$\varepsilon-iR_{10}-L_{40}\frac{di_1}{dt}=0$$ $$L_{40}\frac{di_1}{dt}-i_2R_{60}=0$$ $$i_2R_{60}-R_{30}(i-i_1-i_2)-L_{15}\frac{d(i-i_1-i_2)}{dt}=0,$$ where ##\varepsilon## stands for emf=100V...

I have already solved up to after the switches are flipped, and all the charge is on C1. See the second attached image for a detailed diagram of the situation after the switches are flipped. However, the notes then say that all the charge is trapped between C1 and C2, which I don't understand...

Is there like a rule of thumb, or a simple hack for assigning current direction in circuit analysis? Even when I m consistent with the direction I choose, I still get the wrong answer most of the time. Like 1. Do current source or voltage source affect when choosing current direction? 2...

So far what i figured out is that R2 and R3 are in parallel, R1 and LDR in parallel. And these two parallel circuits are parallel to each other ( tell me if I am wrong) The voltmeter has to read 0 but I am not sure how i can achieve that. Is there a rule where when the resistance of each side...

I assumed the current flows from the 20V so, 20V - 100 (i1) - Ri2 = 0 First loop 20V = 100i1 + Ri2 Second loop +Ri2 + 40V - 200(0.08) = 0 Ri2 = -24 Back to equation 1 20 v = 100i1 + (-24) therefore, i 1 = 0.44 For loop two: i1 - i2 = i3 0.44 - i2 = 0.08 therefore i2 = 0.36 ohms...

My initial attempt had me combining the 40 and 20 ohm resistors in series, then combining the result with the 120 ohm resistor in parallel (top). However, this was incorrect. According to my answering guide, the correct method was to transform the voltage source into a current source, then...

Hi! I've been struggling with this. Original exercise here: Find the value of Iy when R=0. And the value of Vx when R is infinite. For the first part of the question I did this since R=0: I've tried to solve this circuit and I get that Iy and I5 are 0 A, and this can't be possible since Iy...

Homework Statement Find the current in each resistor. (refer to uploaded diagram) Homework Equations ##Kirchhoff's Law: I_s=I_1 + I_2## Mesh analysis method The Attempt at a Solution I'm calling ##I_s## the total current before and after the current splitting up, and ##I_1## and ##I_2## are...

Homework Statement The diagram below shows a circuit where; R1 = 5.0 Ω, R2 = 8.0 Ω, R3 = 1.0 Ω, V1 = 16.8 Volts, V2 = 1.5 Volts, and V3 = 39.6 Volts. What is the value of I1? In solving this problem, initially pick the current directions as shown. If the actual current turns out to be in the...

Homework Statement Homework EquationsThe Attempt at a Solution

1. Homework Statement the problem is my answer for question (a) is not the same as the answer provided by the question, i get 2.81 - j4.49 Ω while the answer demands 2.81 + j4.49 Ω Homework Equations simplifying the circuit, details can be seen below The Attempt at a Solution...

Homework Statement Four identical light bulbs are connected to a battery as shown in the diagram. Switch S is originally closed. If switch S is opened, what happens to the brightness of each bulb? Homework Equations V=IR The Attempt at a Solution - By opening the switch, no more current...

Hi, I was reading KVL and KCL and I read that KVL cannot be applicable to all the situations specially when :- " KVL is applicable on the assumption that there is no fluctuating magnetic field linking the closed loop. While, in presence of changing magnetic field in a High Frequency but short...

How is symmetry used to solve electrical circuits? I have seen several problems in books in which currents in two resistors are said to be equal due to 'symmetry'. That is a concept that I fail to understand and thus cannot apply. In class, we were shown a few circuit diagrams which were...

Homework Statement Given this following circuit: What is the internal resistance of the meter movement ( R_I). This is part of a project I'm doing and I know the equation that gives you the internal resistance in this circuit. $$R_I = \frac{R_sR_p}{R_s - R_p}$$. However, I have no idea how...

Hey guys, in the picture below, the current flowing through R1 is the same flowing through R3 right? And hence we have R1 and R3 in series? In this second picture R2 is going to cancel out because apparently that's what happens when you have a branch containing components parallel with a wire...

In this circuit,first there will be voltage drop in the internal resistance of the voltage source.Mostly,the voltage source is assumed ideal in circuits,however,here a practical voltage source is assumed. So,there will be voltage drop in the internal resistance of the voltage source which will...

Do electrical engineers actually use stuff that is taught in Circuit Analysis classes like Node Voltage Method, Mesh Current Method, Kirchhoff Voltage/Current Law, Source Transformation. All these usually only involve resistors. Are they somewhat altered in a way to analyze circuits with other...

Node Voltage Method or Mesh Current Method.

Homework Statement This problem is taken from Fundamentals of Electric Circuits (chapter 12, problem 15). Homework Equations As shown in the first blue box, I have trouble seeing why after the conversion, Z_Ye will be parallel with Z_Y. I think it's because the voltages 'emitting' from the...

Homework Statement Using Kirchhoff’s rules, (a) find the current in each resistor shown in Figure P28.31 and (b) find the potential difference between points c and f.[/B]Homework Equations [/B] Σ ΔV = 0 (KVL) The Attempt at a Solution [/B] I have been trying to set up a system of equations...

Hi I have the following situation: (Please see attached pic) I want to know if equation (4) i have written is correct. What is confusing me is that, I remember being told in circuit analysis that each energy storage element should have its own state variable. But in this situation when I...

Homework Statement The input signal of the circuit shown below is ##x(t)=2\sin (ω_ot + \pi/6)##. The switch in the circuit is controlled with a digital signal of the form ##s(t)=\sum_{k=-\infty}^{+\infty} (u(t+ε-kT_s) - u(t-ε-kT_s))##, ##\frac{2\pi}{T_s}=800\pi##, ##ε\to 0##, so that when the...

Homework Statement The switch in the circuit in has been closed for a long time. At the switch is opened. a) Find i0 for t>=0 (b) find v0 for t>=0 I don't understand the effect of the switch in the position it is in. It's acting as a short circuit, I think, so presumably the capacitor doesn't...

Hey guys, I have tried and tried to find a start to this problem with no success. My book may have the answer but unfortunately I must be not realizing it. So hopefully I just need a different perspective. Typically I would find the equivalent resistance of the circuit and then begin to...

Homework Statement The problem asks to solve for i1, i2, and i3 using the mesh method in the following circuit: I will also include the link, because I noticed I am having trouble attaching the image to the post: https://imgur.com/a/bBvuLXM I would also like to confirm the answer by solving...

Hi fellow forum-ers :), I have a test in about two weeks where i am going to be given a dtl or ttl circuit which i have to analyse and calculate its function. The professor said that the circuit given to us will always be a useful and existing one meaning he's going to give us some NAND, NOR or...

Hi! I'm working on a project in which a small microcontroller with a max. analog input of 5v takes readings from multiple sensors. I would like to make this input window a bit more versatile, and turned to voltage dividers as a solution. 'Problem is, I'm having a bit of trouble understanding how...

In the problem below, when I use nodes V1 and V2 I get the correct answer of Vo = -2.5v But when I use nodes V1 and Vo I get an incorrect answer. Please explain to me why my latter method did not work. Thanks.

Homework Statement 2. The attempt at a solution Am I doing something wrong? I know it's just voltage division with AC phasors and we have to equate the real parts and imaginary parts to find the unknown, but I feel like the question shouldn't be this hard.

Homework Statement C1 = 4 micro F C2 = 8 mF R1 = 4 ohm R2 = 8 ohm V = 12 Questions : 1) Find current I when S not closed 2) find Vb, when Vc is 0 3) find Vd, when Vc is 0 4) total charge move from B to D Homework Equations Vf - Vi = F.d/q (not sure this below is useful equations) I = E/Z E...

Hello everyone, I hope you could help me with the analysis of this circuit. the output voltage is supposed to be similar to the input but shifted upwards by 20V, so basically it's between 0 and 40V... but why? I mean when the input is 20V, the diode is reverse biased... and the capacitor...

Homework Statement Verify Superposition Principle using Matlab, given a DC source of 100V, an AC source of 50V, 60Hz and three resistances, R1=10 ohms, R2=20 ohms and R3=15 ohms. I created the circuit below and ran the program. Result: Homework Equations None, just running the program...

Homework Statement Identify the type of filter (kinds of frequencies the circuit filters out) analytically 2. The attempt at a solution I believe the top filter to be an inverting low-pass filter, which passes lower frequencies and blocks higher frequency signals. I also think that the...

Hello! I've took a course about Electrical circuits and Networks at the university, and i found out a problem which is uploaded by my professor, and i think he made a mistake! this is the solution i think that the equivalent resistances are wrong (beside Rab), for example if you look at...

Homework Statement http://www.chegg.com/homework-help/questions-and-answers/problem-2-variableh-resistor-r-circuit-fig-p224-adjusted-va-equals-60-v-find-value-r-q8083343 Homework EquationsThe Attempt at a Solution Hi, I attached a pdf file with the problem. My question is, for the lower right...

Homework Statement Consider the following circuit where i(t) is sinusoidal and exists across both components. (1) is an inductor and (2) is a capacitor. The ideal voltmeters measure effective value. What is the value measured by V2: [![enter image description here][1]][1] [1]...

Homework Statement The problem is in this link https://www.chegg.com/homework-help/find-vo-io-circuit-fig-226figure-226-chapter-2-problem-7pp-solution-9780078028229-exc Homework Equations 3. The Attempt at a Solution [/B] 15=[io/3]+[io/3]+ [vo/12] I got this equation for the problem...

Homework Statement Pic A, what's the I2? Pic B, what's the current across a-b ? Homework Equations V = I*R Voltage in series is different, the current is the same Current in parallel is different, the voltage is the same The Attempt at a Solution from Pic A, I found that I1 = 1A, I3 = 1A...

should you only apply the test sources when there are only independant sources in the circuit. Also would it be valid to zero all dependant source so that you are only left with independant sources and then apply the test source. It seems like i am always applying open and short circuit...