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A circuit is a path which electrons from a voltage or current source flow. Electric current flows in a closed path electric circuit. The point at where electrons enter a circuit is called the source of electrons. The point at which the electrons leave the circuit is called the return or earth ground. The part of a circuit which is between the electrons’ staring point and the point where they return to the source is called an electrical circuit load.

Electrical circuits usually use alternative current (AC) sources. The load may be as simple as those of electrical appliances like refrigerators or quite complicated loads such as hydroelectric power generating stations.

Electronic circuits use low voltage direction current (DC) sources. The load of an electronic circuit may be as simple as a few resistors, capacitors and a lamp all connected together when creating a digital camera, or as complicated as connecting thousands of resistors, capacitors and a transistor to create a microprocessors.

Circuits can be complicated. However, they can be modeled by drawing the connections of all the component parts in the circuit’s load which makes it easier to understand. Drawing the electronic circuits are called a circuit diagram. Drawing electrical circuits are called a wiring diagram. 

Categories within Circuits


Postings: 104

Alternating current is when the flow of electric charge periodically reverses direction.


Postings: 95

Direct current is the unidirectional flow of electric charge.


Postings: 180

Resistance is when a material's opposition to the flow of electric current.

Kirchhoff's Current Law

Postings: 14

Kirchhoff's Current Law states that the current entering any junction is equal to the current leaving that junction.

Growth of current in a C-R circuit

Three capacitors each with capacitance C and a parallel combination of two resistances R each are connected in series with an ideal battery of emf V as in figure. a) What is the time constant of the circuit? b) If the switch is closed at time t = 0; find an expression for the current in the circuit as a function of time. c)

Class B amplifier distortion theory question

What is the primary source of distortion with a Class B amplifier? What are some ways the distortion can be minimized and discuss the trade offs that exist when implementing these distortion minimizing methods?

Summary of Class C amplifier design and matching networks

Question: In radio frequency (RF) circuits used for portable applications, power efficiency is extremely important. For this reason, Class C power amplifiers are used wherever practical. There are some limitations in using Class C amplifiers, as we discussed in class. Identify these issues. Another consideration for a pow

Capacitance and Inductance

1. Assume that two parallel plates with a surface area of 50,000 mm^2 are separated by 0.1 mm. a) Determine the capacitance if the plates are separated by air. b) Determine the capacitance if the plates are submerged in de-ionized water. c) Which di-electric material allows the plates to store more energy. 2. Determine t

Quality Assurance: Printed Circuit Boards

At ZYZ Company, a custom manufacturer of printed circuit boards, the finished boards are subjected to a final inspection prior to shipment to its customers. As XYZ's quality assurance manager, you are responsible for making a presentation to management on quality problems at the beginning of each month. Your assistant has analyz

Loop Analysis and Node Analysis: Current and Voltage

** Please see the attached file for the complete problem description ** Solve using any method including Node Analysis, Source transformation, Voltage Divider Rule, Current Divider Rule. Whatever makes it the simplest.

OP AMP circuit analysis

For the circuit below, perform the following: 1. Given a voltage gain of -10, determine the value of R2. 2. Calculate the peak-to-peak value of Vout and rms value of Vout. Please refer to the attachment.

Circuit Nodal Analysis

I'm having trouble understanding nodal analysis. Please help. Please refer to attachment for full question details and circuit drawings. 1. Given that the current flowing through R1 is 2A and the current flowing through R2 is 4A, determine the current flowing through R3. 2. Based upon the given and calculated values,

Inductive Crosstalk without shielding

The mutual inductance between the two circuits shown in FIGURE 2 is 20 nH. It may be assumed that (R1 + R*L1) >> w*L1 and that (R2 + RL2) >> w*L2. (a) Estimate the crosstalk voltage at the load of circuit B when the signal source of circuit A is V1 = 100 mV at 1 GHz. (b) Plot the crosstalk voltage (at the load of circuit

Series RC circuit response to a unit-step signal

A unit-step function u(t) can be considered a causal constant source (e.g. a battery in a circuit if the units of u(t) is volts). (a) From basic principles consider the response of an RC circuit to u(t) - that is, a battery connected in series with the resistor and the capacitor. Plot what would be the voltage across the capa

Electric Circuits Voltage and Resistance

A circuit consists of a load of a 50 ohm resistor in parallel with a 30 ohm resistor. The resistors are connected to a 10 volt battery. a. What is the voltage across the 50 ohm resistor and the current through the 50 ohm resistor? b. What is the voltage across the 30 ohm resistor and the current through t

Electric Circuits Expression

Problem 36.36 Part A For an circuit, find an expression for the angular frequency at which . ANSWER: Answer not displayed Part B What is at this frequency? ANSWER: Answer not displayed Part C What is if the crossover frequency is ? ANSWER: Answer not displayed rad/s

Radio Tuning Circuit

A Radio Tuning Circuit A radio can be tuned into a particular station frequency by adjusting the capacitance in an L-C circuit. Suppose that the minimum capacitance of a variable capacitor in a radio is 4.18 . Part A What is the inductance of a coil connected to this capacitor if the oscillation frequency of the L-C circu

Maximum and minimum oscillation in a circuit.

A 2.0 mH inductor is connected in parallel with a variable capacitor. The capacitor can be varied from 100 pF to 200 pF. Part A What is the minimum oscillation frequency for this circuit? ANSWER: Answer not displayed Hz Part B What is the maximum oscillation frequency for this circuit? ANSWER: Answer not displ

OSI Model

Discuss the role of the physical layer, data link layer, and network layer in network transmissions. For the physical layer, contrast circuit switching and packet switching. For the data link layer, discuss sliding window protocols and the data link layer in the Internet. For the network layer, discuss virtual circuits and datag

Inductive Circuit: Real, Apparent, and Reactive Power

** Please see the attachment for the circuit illustration ** Please help with the given assignment: For the circuit given in the attachment, the power factor is 0.72 lagging and the power dissipated is 375 W. Determine the: (i) apparent power, (ii) reactive power, (iii) the magnitude of the current flowing in the circuit

Mesh analysis techniques to determine currents

A. Using Maxwell's circulating currents, calculate the three complex currents. Assume an angular frequency of 2.2 Mhz. b. Sketch a phasor diagram showing all the currents and the two voltages V1 and V2. Please refer to the attachment for circuit diagram.

Jumper cables: determine current in starter, battery

1. Jumper cables are connected from a fresh battery in one car to charge a dead battery in another car. The figure below shows the circuit diagram for this situation. While the cables are connected, the ignition switch of the car with the dead battery is closed and the starter is activated to start the engine. (Let R = 1.35 O an

BJT: capacitor size, voltage gain and impedance

Please see the attachment for circuit diagram, where R1 =91k ohms R2 = 20k ohms Rc = 5K ohms Re = 1k ohms. Now add a capacitor from emitter to ground, and size it to give a 3 db attenuation in gain to the collector at 1 kHz, relative to gain at a higher frequency where the gain does not change with frequency. What size

Detailed solution to show how calculate circuit and power parameter associated with Magnetron Drive Circuitary and Radar pulse produced. Calculation involve RF Electronics and Theory

This solution deals with the analysis of a given Magnetron Drive Circuit to derive the circuit characteristics as applied to a resulting Radar pulse. Circuit parameters are given including Delay Line parameters and from this such things as the number of turns on the secondary winding of the drive transformer, the pulse period an

Charging and discharging a capacitor in an RC circuit

A capacitor C is charged from a 10V supply through a resistor, and is then fully discharged again so that its voltage cycles from 0 to 10V and back to 0. Find the energy dissipated in the resistor, the energy stored in the capacitor, and energy drawn from the voltage source in this cycle.

Mesh and Nodal Analysis of Circuit

Use the values given in the table to determine the current I in the circuit: a) by mesh analysis b) by nodal analysis Please refer to the attachment for the table and the circuit.

Probability of useful life of an electrical component

The useful life of an electrical component is exponentially distributed with a mean of 2,500 hours. a. what is the probability the circuit will last more than 3,000 hours b. what is the probability the circuit will last between 2,500 and 2,750 hours. c. what is the probability the circuit will fail within