All dc circuit analysis the determining of currents, voltages and resistances throughout a circuit can be done with the use of three. This ebook was written as the sequel to the ebook titled dc circuits, which was written in 2016 by chad davis. In this manual, the electron flow convention is used. If v is abruptly changed, then the current will have an infinite value that is practically impossible. Ac circuits as the name alternating current implies are simply circuits powered by an alternating source, either voltage or current. In other words, it is a measurement of the work required to move a unit charge between two points. The 11th edition of electronic devices and circuit theory by robert boylestad and louis nashelsky offers students complete, comprehensive coverage of the subject, focusing on all the essentials they will need to succeed on the job. I direct current dc modern life could not exist if it were not for electricity and electronics. Presentation features, conceptual content, and use of analogies. Chapter 27 questions 1, 3, 5 chapter 27 problems 7, 19, 49 wileyplus assignment. Superposition theorem is one of those strokes of genius that takes a complex subject and simplifies it in a way that makes perfect sense.
This law states that the current in a circuit is directly proportional to the potential. Describe in terms of circuit values the circuit condition needed for maximum power transfer. Fundamentals of electricity using the simple circuit shown, assume that the voltage supplied is 12 volts, and the resistor provides six ohms of resistance. The manual contains sufficient exercises for a typical 15 week course using a two to three hour practicum period. The transient behavior of rc circuits is also tested.
The load resistor is connected in series, parallel or seriesparallel combination as per requirement. As we have learned in introduction to electricity, there are two forms of electricity used for commercial use to the public, ac current and dc current. Their effect is to reduce the available voltage to be applied across the other. An electrical circuit is a combination of two or more electrical components which are interconnected by conducting paths.
Network is an interconnection of elements or devices, circuit is a network providing one or more closed paths. Theory overview the dc steady state response of rl and rc circuits are essential opposite of each. The most fundamental law in electricity is ohms law or vir. Network theory response of dc circuits tutorialspoint. The following topics are covered in these circuit theory notesebook. Batteries, electronic circuits, led lights, generator excitation systems and rotors, dc transmission lines and much more. The voltage on the left hand 10 ohm resistor is flowing out of the top terminal of the resistor. In this way, we eliminate the need for the socalled physical considerations traditionally used to resolve ambiguities. The history of electricity starts more than two thousand years ago, with the greek philosopher thales being the earliest known researcher into electricity. Objective in this exercise, the dc steady state response of simple rl and rc circuits is examined. Introduction electric circuit theory and electromagnetic theory are the two fundamental theories upon which all branches of electrical engineering are built. Volume 2 of 4 module 3 dc circuits this module introduces the rules associated with the reactive components of inductance and capacitance and how they affect dc circuits. If the flow of electron does not change his path and is in unidirectional flows or movements inside a circuit it is called as dc or direct current.
In other words, the equivalent capacitance for a parallel combination of capacitors has the same mathematical form as that of the series combination for resistors. Dc circuits open textbook library center for open education. Basic dc theory circuit exchange international cxi. This book covers direct current dc circuit theory and is broken up into three modules. Relationship between voltage current and resistance. Basic ac theory i i direct current dc alternating current ac i i figure 1.
Seriesparallel dc circuits worksheet dc electric circuits. Electric theory, quantities and circuit elements current direct current dc flows in only one direction. Generating dc dc can be generated in a number of ways. There are two types of electricity direct current and alternating current, i.
State the meaning of the term source resistance and describe its effect on a circuit. This ebook covers alternating current ac circuit theory as well as a brief introduction of electronics. The humble transistor q1 emitter e collector c base b transistor basics emitter to base junction is forward. Circuit theory is an approximation to maxwells electromagnetic equations f. Introduction to dc circuits electric voltage and current. Pdf an analysis of dc circuit theory content in an engineering. The currents i2 and i3 and the unknown resistance, r can all be calculated, using basic dc theory. From the given circuit, find the voltage across ab, cb, and db. The same current flows through each part of a series. Circuit theory i capacitors and inductors michael faraday 17911867 english chemist and physicist, discovered electromagnetic induction in 1831 which was a breakthrough in engineering because it provided a way of generating electricity. This text book covers the basics of dc circuit analysis. In case of direct current, the polarity will never reverse or changed with respect to time, whereas the flow of current can vary with time. Enriched with rich pedagogy, this book is a useful tool for both students and teachers alike.
Construction of ac circuits and working of ac circuits. Tippens, professor of physics southern polytechnic state university a powerpoint presentation by. Conventional flow will be used from this point on in these training modules unless otherwise. Kuh meant for the undergraduate students taking the course on circuit theory, this book provides a comprehensive exposure to the subject. Fundamentals of electricity despite the fact that it has been positively determined that electron flow is the correct theory, the conventional flow theory still dominates the industry. Either theory can be used as long as the orientations are correct. March16,20 onthe28thofapril2012thecontentsoftheenglishaswellasgermanwikibooksandwikipedia projectswerelicensedundercreativecommonsattributionsharealike3. Direct current dc direct current is a bit easier to understand than alternating current.
The direction of current flow is as indicated by the arrows. Power in ac circuits ipower formula irewrite using icos. Therefore, in the ac circuit the maximum current required is 1. Here you will learn to draw the ac load line, extract the t and. Circuit theory i superposition the superposition principle states that the voltage across or current through an element in a linear circuit is the algebraic sum of the voltages across or currents. Power, which is defined as the rate at which work is done or energy is used, is measured in watts 1 watt 1 jsec. Going on to the fifth chapter we discuss about the operation of the transistor in ac. Seriesparallel dc circuits dc electric circuits pdf version.
Direct vs alternating current distribution systemsthat are far more ef. When a dc voltage is connected across an inductor, a current is made to flow through the inductor. The unit of capacitance, the farad, was named in his honor. Science 14 lab 3 dc circuits theory all dc circuit analysis the determining of currents, voltages and resistances throughout a circuit can be done with the use of three rules. Electrical dc circuit definition of electrical circuit.
Bakshi a guideline for student to understand basic circuits analysis, network reduction and network theorems for dc and ac circuits, resonance and coupled circuits, transient response for dc circuits, three phase circuits. It is very important to remember that voltage can exist without current as it is the voltage difference between two points or potential difference but current. Ac is the major source of power used by most all customers, residential, commercial and industrial. Basic dc theory basic dc circuit calculations step 3. Define open and short circuits and describe their effects on a circuit. Chapter 28a direct current circuits a powerpoint presentation by paul e. Science 14 lab 3 dc circuits theory all dc circuit analysis the. Thus, the circuit theory or analysis helps to understand the circuit behavior or characteristics by finding out the voltages and currents in various elements in a circuit by using different.
Pdf electronic devices and circuit theory by robert. A simple dc circuit is shown in the figure below which contains a dc source battery, a load lamp, a switch, connecting leads, and measuring instruments like ammeter and voltmeter. To explain the details of why this is so, a bit of background knowledge about ac. An analysis of dc circuit theory content in an engineering textbook. In other words, the linear circuit looking into terminals ab can be replaced by an equivalent circuit consisting of a voltage source vth in series with an equivalent resistance rth, where vth is the open circuit voltage vn and. Basic definitions and dc circuits higher education. E voltage volts i r or current amps resistance ohms figure 10. When we see a value such as 10 volts, it is a measurement of the potential difference between two. In case of the circuit where free electrons are flowing, it is also true.
Even though module 1 is not very difficult, it forms the foundation for more complicated topics in modules 2 and 3 so it is important to have a firm grasp of. Circuit theory i superposition the superposition principle states that the voltage across or current through an element in a linear circuit is the algebraic sum of the voltages across or currents through that element due to each independent source acting alone. A circuit that can be ac or dc is the combination of active elements power supply sources and passive elements resistors, capacitors and inductors. This is a very basic definition of electrical circuit dc circuit. A branch represents a single element such as voltage source or a resistor. Compute circuit and component power in series, parallel, and combination circuits. All voltages and currents have polarity as well as magnitude.
But for now, well just concern ourselves with dc circuits. Rather than oscillating back and forth, dc provides a constant voltage or current. Generate the dc voltages needed for most electronics starting with the ac power that comes through the power line 120 v rms 9df 9sin 7 w f 60 hz t 16. Fundamentals of alternating current in this chapter, we lead you through a study of the mathematics and physics of. Circuit theory is an approximation to maxwells electromagnetic equations by assuming. Introduction to electrical theory and dc circuits 315. Chapter 14capacitors 527 dc version of an rc circuit figure 14. The outcome is an internallyconsistent theory of circuits, which produces results that are correct in both magnitude and phase. We can get dc voltage by converting this ac to dc or from batteries, solar panels, various power supply units as well as phone chargers. The sum of the currents entering a junction is equal to the sum of the currents leaving that junction. The circuit symbol for an alternating voltage source is a circle with a sine wave. This laboratory manual is intended for use in an ac electrical circuits course and is appropriate for either a two or four year electrical engineering technology curriculum.
Even though module 1 is not very difficult, it forms the foundation for more complicated topics in modules 2 and 3 so it is important to have a firm grasp of all module 1 topics before moving on. Module 1 covers the basics for circuits that include dc sources voltage or current and resistors. Electrical dc series and parallel circuit electrical4u. To determine the current, use the following formula. The humble transistor q1 emitter e collector c base b transistor basics emitter to base junction is forward biased normally collector to base junction is reverse biased normally transistors are current operated devices, so. The sum of the currents entering a junction is equal to the sum of the. An alternating current or voltage, is one in which the value of either the voltage or the current varies about a particular mean value and reverses direction periodically. Module 2 basic dc theory this module describes the basic concepts of direct current dc electrical circuits and discusses the associated terminology. Since only dc sources are used in the first ebook, details of ac signals such as sinusoidal. Unfortunately, the scientific theories explaining why certain materials conduct and others.
Science 14 lab 3 dc circuits dartmouth college home. As useful and as easy to understand as dc is, it is not the only kind of electricity in use. This laboratory manual is intended for use in a dc electrical circuits course and is appropriate for two and four year electrical engineering technology curriculums. This is an interesting seriesparallel circuit problem to solve, and it shows once again how a good understanding of circuit theory enables unmeasured variables to be inferred. There are electrical elements that do not follow this pattern. Najmabadi, ece 65, winter20, intro 215 a circuit is made of a bunch of elements connected with ideal i. General electronic circuits operate on low voltage dc battery supplies of between 1. Electrical fundamentals introduction to direct current dc theory. Electrical science module 2 basic dc theory ntc sites.
Part i is a barebones introduction to basic electronic theory while part ii is designed to be a practical manual for designing and building working electronic circuits. Superposition theorem dc network analysis electronics. Direct current dc electrical circuits by ron kurtus. Chapter 27 questions 1, 3, 5 chapter 27 problems 7, 19, 49. Setting the standard for nearly 30 years, this highly accurate text is supported by strong pedagogy and content that is ideal for new students of this rapidly. The v is for voltage, which means the potential difference between two charges. V3 60 volts the voltages of v1,v2, and v3 in example 2 are known as voltage drops or ir drops. A theorem like millmans certainly works well, but it is not quite obvious why it works so well. This ebook of circuit theory is in pdf format which is easily downloadable. Introduction to electrical theory and dc circuits a suncam online continuing education course. Formula for current in the workplace another example of a simple dc. Circuit theory pdf lecture notes, ebook free download for.