circuits

  1. J

    Engineering Calculating the gap of a parallel plate capacitor

    I've been given this question for my TMA2, I've tried looking at the learning material but it gives no information on how to calculate the gap? Does anyone have a formula for this? Or can someone point me in the right direction? Thanks
  2. A

    Rectified Current Through an Inductor

    Hello, I need to find the magnetomotive force (mmf) of an inductor using NI (turns multiplied by amperes). The set up is pretty simple, AC power supply set at 24 VAC goes through a full wave rectifier (4 diodes) and into an inductor. If the inductor has a resistance of 47 Ohms, it looks like...
  3. Oannes

    Finding the Current Through a Resistor (Working With Parallel and Series)

    Here is the actual question. And here is my attempt at a solution In Summary I did the following Found the Equivalence Resistance to Be 5.9 ohms and the Current throughout the entire resistor to be 1.53 Amperes Worked backwards from my resistor simplifications. When the resistors were in...
  4. Salman Ali

    Question about a Flip Flop circuit

    Hello! I am confused in a question I found on youtube. I have uploaded the screen shots. He told that with respect to S and R we have to write the change from Q to Q+( next state). But I am not getting it. How he wrote Q+ states?Is he considering that when S=1 , we have to set the circuit i.e on...
  5. DaynaClarke

    Resistors in Parallel or Series?

    Given that they're all on the same branch, I had assumed that they were in series with one another. But with the middle resistor having being on the middle of three branches, it looks parallel. Like I said, I have a feeling it's in series (making the answer 3R). This question is from a past...
  6. Salman Ali

    Priority Encoders

    Hello guys! I am getting confused in drawing the circuit for a priority encoder. Because I saw some youtube videos and also on google , they all are drawing 4 to 2 priority encoder differently.These both are 4 to 2 priority encoders.
  7. D

    Total equivalent resistance of a combined circuit

    I attempted to solve the problem by following the positive terminal of the battery and I realized that Resistor R1 has a different path than R2+R3+R4. I came to the conclusion that R1 is in parallel with R2+R3+R4. The series connection with R2,R3,R4 would be 30 ohm total by adding the three...
  8. P

    Finding the current and voltage for each resistor

    1. Homework Statement Moderators note: link removed. All images should be uploaded to PhysicsForums. 2. Homework Equations V=IR Series in parallel Series in current 3. The Attempt at a Solution I managed to get the current and voltage of R1 and R2. I've been trying to get the next one...
  9. D

    How do I tell if the Wien bridge oscillator I built works

    I built a wien bridge oscillator. But how do I tell if it works? I am very new to building circuits. I recently Starting making circuits on a breadboard. I have not taken any Electronics class. I am trying to learn how to do this.
  10. Castello

    Thevenin equivalent by source transformation

    1. Homework Statement Find the Thevenin equivalent at terminals a-b V1 = 70V V2 (dependent) = 4Vo R1 = 10Kohm R2 = 20Kohm 2. Homework Equations ##V=RI## ##1/req = 1/r1 + 1/r2 + ... +1/rn## 3. The Attempt at a Solution Found the current i = 1mA by KVL using Vo = 10ki then did source...
  11. L

    How would I solve this Mixed Circuit?

    1. Homework Statement The following circuit is given, and all voltage, current, resistance and power must be found for each resistor. I have found the following information: Vsrc = ? Isrc = .5A Rsrc = ? Psrc = ? V1 = ? I1 = .5A R1 = ? P1 = ? V2 = 2.5V I2 = .25A R2 = 10 P2 = .625W V3 =...
  12. archaic

    AC Circuit and Thevenin's theorem

    1. Homework Statement I'm asked to find the thevenin equivalent circuit, the load being ##R_1## ##e(t)=E_0\cos{(\omega t)}## ##R_1=1k\Omega \ R_2=R_3=1k\Omega## ##C=220nF \ f = 250Hz \ E_0=10V## 2. Homework Equations 3. The Attempt at a Solution ##Z_{th} = Z_{R_2}//(Z_c+Z_{R_3}) =...
  13. C

    Symmetry in Electrical Circuit Analysis

    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...
  14. Lapse

    Engineering Design Circuit to Convert Current to Voltage | LTSpice Also

    Hello, We just finished up midterms and I actually did well--got an A. However, somehow between the midterm (class before last) and last class we jumped to creating a circuit with a diode. I am pretty lost. 1. Homework Statement 2. Homework Equations Voltage / Current = Resistance 3...
  15. J

    Which circuit shows the correct connection and values?

    1. Homework Statement Question: For the circuits shown in Fig. 6, voltage meters and ampere meters are used to measure the voltage across the load and their current flow. If the Red Probe is plugged into the “+” terminal of the voltage meter and ampere meter, which circuit(s) show both the...
  16. J

    Engineering AC Source driving an RLC circuit...

    1. Homework Statement 10 v, 100 hz goes into a circuit of a 1o resistor, a 1o inductive reactance and a 1o capacitive reactance that are in series. What is the current. What is the V across the cap. 2. Homework Equations and the attempt at a solution So I know I = V/Z and Z = sqrt( R^2...
  17. D

    I What counts as a circuit?

    I have to construct suitable circuits to show the operational principles of some sensors: pH meter, sound, light and temperature. Would these count as circuits? or diagrams? (I'd say diagrams). I am finding it hard to find circuits showing how sound sensors and pH sensors work etc and the ones...
  18. F

    Engineering Unknown resistor in a series-parallel circuit

    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...
  19. D

    Loss of energy and energy loss prevention in circuits

    1. Homework Statement why is there a loss of energy in DC circuits and power loss is reduced in AC when transmitted 2. Homework Equations 3. The Attempt at a Solution Loss of energy in a DC circuit is due to the resistance of the wire cauing the wire to heat up therefore energy is being...
  20. D

    What does W=VIt show?

    1. Homework Statement I have to explain the equation W=VIt and apply it to a circuit. But I do not undertsand what the equation shows. 2. Homework Equations W=VIt 3. The Attempt at a Solution My rough guess is : work done is equal to the time (t) taken for 1A of current to flow at 1V
  21. lbwet

    What's the total resistance in this circuit?

    1. Homework Statement https://imgur.com/3H3pCkD R is the resistance of each resistor, determine total resistance in the circuit. (see the image in the link above) 2. Homework Equations R=1/R₁+1/R₂+1/R₃+... (in parralel circuit) R=R₁+R₂+R₃... (in series circuit) 3. The Attempt at a...
  22. E

    Engineering Opamp circuit question

    1. Homework Statement http://www.chegg.com/homework-help/questions-and-answers/ideal-opamp-find-v0-terms-vs-need-help-solving-vp-firstly-understanding-parts-q8278769 2. Homework Equations I am having difficulties with this problem. It asks to find vo in terms of vs. For the gain, I got an...
  23. kstorm19

    Question about complex power in three phase circuits

    1. Homework Statement Assume that the two balanced loads are supplied by an 840-V rms 60-Hz line. Load #1: Y-connected with 30+j40 Ω per phase, Load #2: balanced three-phase motor drawing 48 kW at a power factor of 0.8 lagging. Assuming abc sequence, calculate the complex power absorbed by the...
  24. kcombs

    RC Circuit Problem

    1. Homework Statement Suppose a 120 micro-farad capacitor from a camera flash unit retains voltage of 210 V when an unwary student removes it from the camera. If the student accidentally touches the two terminals with his hands, and if the resistance of his body between his hands is 1.8...
  25. rocky4920

    FInding current in parallel and series circuits

    1. Homework Statement a. What is the net resistance in the circuit? b. What is the current through the 4 Ω resistor? c. What is the voltage drop across the 3 Ω resistor? 2. Homework Equations R12 = R1 +R2 R34 =R3 + R4 1/Rt = 1/R12 + 1/R34 I3=I4 3. The Attempt at a Solution a) R12...
  26. F

    B Discharge in a DC RC circuit and Kirchhoff's Loop Rule

    Hi all, I think this issue periodically resurfaces in PF. I have found a similar discussion in this closed post and possibly others. I'm posting this because I'd like to check my understanding, if anyone is available to provide some furtherinsight. So I'm trying to gather a "overall"...
  27. E

    Engineering Help with finding the power in this circuit

    1. Homework Statement http://www.chegg.com/homework-help/questions-and-answers/interconnection-fig-p25-valid-find-total-power-developed-circuit-interconnection-valid-exp-q22345911 It asks if the circuit is valid, which I assume it is. It asks for the power developed 2. Homework Equations I...
  28. R

    Internal Resistance of a Car Battery

    1. Homework Statement An automobile battery has a terminal voltage of 12.8 V with no load. When the starting motor (which draws 90A) is running, the terminal voltage drops to 11.0 V. What is the internal resistance of the battery? 2. Homework Equations V= EMF- Ir 3. The Attempt at a Solution...
  29. F

    I Please suggest whether I should use delta or dx method.

    I previously made a derivation of Neumann potential. It can be found in the pdf file below. I originally made it in the ##dx## method. It involved equations like ##dm=I dS##. My maths teacher told that such an expression has no meaning, at least in elementary calculus. However I argued that my...
  30. M

    Question about output voltages and impedances

    1. Homework Statement 1. For the first measurement, a load resistance Rload = 119Ohms results in an output voltage V(OUT) = 11Volts. For the second measurement, Rload = 11Ohms results in an output voltage V(OUT) = 3.2Volts. From these two measurements, determine the output voltage V(OUT) when...
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