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Kirchhoff's Voltage Law

Kirchhoff’s Voltage Law states that the total voltage around a closed loop must be zero. This is the result of the electrostatic field being conserved. If Kirchhoff’s Law were not true, then we would travel around a closed loop and the voltage would be indefinite.

∑V = 0

The Kirchhoff’s voltage equation is obtained by traversing a circuit loop in either direction and writing down unchanged the voltage of each element whose “+” terminal is entered first and writing down a negative of every element’s voltage where the minus sign is met. The loop must state and end at the same point however it does not matter where you start on the loop.

The current direction must be assumed. The assumed current creates a voltage across each resistor and fixes the position of the positive and minute signs so that the passive sign convention is obeyed. The assumed current direction and polarity of the voltage across each resistor must be in agreement with the passive sign convention for the analysis to work

Circuit Theory

Please review the below questions and give fully worked out answers and explainations where appropriate so it can assist in my further understanding of electrical and electronic circuit theory for complex simultaneous equations, mesh analysis, and Kirchoffs Laws.

Analysis of AM circuit

A third year engineering student is designing a modulating circuit in a simulator. The completed schematic is shown in Figure Q4. When he simulates the output, the circuit seems to be working fully. He now takes a demodulating circuit which he has successfully designed and tested previously on a similar modulator and finds that

Limiting Value of the Charge

A circuit contains an electromotive force [E(t)], a capacitor with capacitance of C Farads, and a resistor with a resistance of R ohms. The voltage drop across the capacitor is Q/C where Q is the charge in Coulombs, so Kirchoff's Law gives R * I + Q/C = E(t) But I = dQ/dt, so R * dQ/dt + 1/C * Q = E(t) If the resista

current in RL circuit..

An electric circuit with an ohmic resistor R and an inductance L will exhibit a certain delay in approaching the (asymptotic) saturation current I_infinity=U/R in response to a voltage source U. Using Kirchoff's circuit laws, electrical engineers have proposed the equation dI/dt=-R/L I+U/L for describing the time dependence I(

LC Circuit With A Battery

There is a LC circuit with a battery with emf (E). The battery is connected in series with the inductor and the capacitor. At t=0 the charge of the capacitor is Q and the current in the circuit is 0. a) Draw the circuit and put the battery wherever you want. b) Write the 2nd law of Kirchhoff for the circuit. c) Find the cha

Autotransformer

Please show as much working as possible and comment where possible. Please refer to attached diagrams for complete questions and mentioned figures. 1. The diagram below shows an autotransformer represented as two separate inductors, L1 and L2, magnetically coupled with a coupling coefficient k. a) Apply Kirchhoff's volta

Apply Kirchhoff's voltage law to the input and output circuits

Please refer to the attachment for the mentioned figures. FIGURE 6(a) shows a particular type of transformer, called an autotransformer. The autotransformer has just one winding that has three electrical connection points called taps. One tap forms a common connection that is connected to both the source and the load. In an a

Unknown voltages and currents.

Please see the attached file - Do I use Kirchhoffs law - I get confused between that and Ohms law and when I need to apply Kirchhoffs.

Electrical Circuit Problem

Given the following Electrical Circuit, which statement below is true? 1. The voltage across R3 equals the battery voltage 2. The current through R2 is greater than the current through R1. 3. The current through R1 equals the current through R3. 4. The voltage across R5 equals the voltage across R4. 5. The current throug

Applying Kirchoff's Laws

The diagram of the circuit in the attached file is composed of two batteries (e1 = 9 V and e2 = 6 V) and four resistors (R1 = 110 ohm, R2 = 40 ohm, R3 = 50 ohm, and R4 = 50 ohm) as shown. (a) What is the current I1 which flows through R1? (b) What is the current I3 that flows through R3? Because of the presence of batte

Charge Passes Through the Circuit

1. The current flowing through a circuit is i(t)= 4t+3 A. How much charge passes through the circuit element between 0 and 2 seconds? 2. Three circuit elements are joined at a node in a circuit. Two amps are flowing into the node from one element, and seven amps are leaving the node and flowing into the element two. How many

KCL and Ohm's Law

(I have attached a picture of the problem.) With reference to Problem 2.7, use Kirchoff's current law and Ohm's law to find the resistances R1, R2, R3, R4, and R5 if R0=2 ohms. Assume R4=(2/3)R1 and R2=(1/3)R1. Problem 2.7 was about finding the currents using Kirchoff's current law knowing that i0=2A, i1=-4A, iS=8A and Vs

Charge, Current, Potential Difference

In the attached circuit diagram: 1) Find the magnitude of the charge in the upper branch. 2) Find the magnitude of the current in the middle branch. 3) Find the magnitude of the current in the lower branch. 4) What is the potential difference V_ab of point a relative to point b?

Current, voltage, power

Please see attached. Need assistance with problems 6 and 2 showing all equations used and all math used, symbols, numbers etc and do each step by step. Adult learning here! Thanks! Questions: (1) How much energy does a 100 W electric bulb consume in 2 hours? (2) A store element draws 15 A when connected to a 130 V line.

Circuits and currents: In series, in parallel for battery connection

1. You connect a number of identical light bulbs to a flashlight battery. What happens to the brightness of each bulb as more bulb as more bulbs are added to the circuit if you connect them in a) series; b) parallel? Will the battery last longer if the bulbs are in series or parallel? 2. In a two-cell flashlight, the batteri

Circuitry Problems

1) In the following circuit, all bulbs are identical. The voltage drop across bulb A is 10.0 volts A) Rank the bulbs in terms of brightness, starting with the brightest. B) Find the voltage between points 1 and 2. State: "the voltage at point 1 is ________ volts relative to point 2." (In other words, if I use my voltmeter, c

Circuit Calculation

For the attached circuit, find Vx, I1, and I2. a) Vx=5V, I1=0.5A, I2=0.5A b) Vx=10V, I1=0.5A, I2=1A c) Vx=2.5V, I1=0.75A, I2=0.25A d) Vx=7.5V, I1=0.25A, I2=0.75A

Electronics: Using Voltage

Instructions: When asked to "Derive an Expression", do so providing proof. In schematics, ground and chassis may be assumed to be common, unless specifically stated otherwise. Unless otherwise specified, assume that Op-Amp supply voltages are. Hi, I need assistance with the following practice problem in the attachment. I am