Topic 5.2 Heating Effect of Electric Currents


 Louise Lawson
 4 years ago
 Views:
Transcription
1 Topic 5.2 Heating Effect of Electric Currents Kari Eloranta 2017 Jyväskylän Lyseon lukio International Baccalaureate February 14, 2017
2 Topic 5.2 Heating Effect of Electric Currents In subtopic 5.2 we study DC circuits. DC circuits are modelled with circuit diagrams, which are idealisations of real, physical circuits. Circuit symbols are listed on page four in the Data Booklet.
3 5.2 Most Commonly Used Circuit Symbols (ideal) wire resistor switch variable resistor A V ammeter, internal resistance R int 0Ω voltmeter, internal resistance R int (ideal) cell lamp battery potentiometer Figure: Two equivalent circuit diagrams for the study of (I,V ) properties of a lamp.
4 5.2 (I,V ) Characteristics of a Lamp V V A I Figure: The circuit diagram for the (I,V ) properties of a lamp. Voltmeter is in parallel with the lamp, and ammeter is in series with the lamp. Conventional electric current I flows from the positive terminal into negative terminal (in opposite direction to the electrons).
5 5.2 (I,V ) Characteristics of a Resistor (Ohm s Law) V R V A I Figure: The circuit diagram for the (I,V ) properties of a resistor. Adjustable voltage source provides changing electric potential difference to the circuit.
6 Kirchhoff s Laws 5.2 Kirchhoff s First Law In 1845 German physicist Gustav Kirchhoff ( ) suggested two laws that give us a way of determining electric currents and electric potential differences in a DC circuit. Kirchhoff s First Law The sum of electric currents entering a junction is equal to the sum of the currents leaving the junction. Kirchhoff s First Law is a natural consequence of the conservation of electric charge. If the currents entering a junction are positive, and the currents leaving the junction negative, the sum of the currents is zero: ΣI = 0 (node rule) (1)
7 Kirchhoff s Laws 5.2 Kirchhoff s First Law I 3 I 1 I 4 I 2 I 5 Figure: Kirchhoff s First Law. The sum of the electric currents entering the junction equals the sum of the currents leaving the junction (ΣI = 0 I 1 + I 2 = I 3 + I 4 + I 5 ). This is a result of the conservation of electric charge.
8 Kirchhoff s Laws 5.2 Kirchhoff s First Law I 3 I 1 I 4 I 2 I 5 Figure: Kirchhoff s First Law. The sum of the electric currents entering the junction equals the sum of the currents leaving the junction (I 1 + I 2 = I 3 + I 4 + I 5 ).
9 Kirchhoff s Laws 5.2 Kirchhoff s Second Law Kirchhoff s Second Law The sum of electric potential differences along any closed loop in a DC circuit is zero. Kirchhoff s Second Law is a consequence of the conservation of energy: any electric potential change equals the change in electric potential energy per unit charge. If the electric potential drops are negative in the direction of electric current, and increases positive, the sum of the changes in electric potentials along any closed loop in a dc circuit is zero: ΣV = 0 (junction rule) (2)
10 Kirchhoff s Laws 5.2 Kirchhoff s Second Law R 1 R 2 V
11 Resistance 5.2 Resistance Resistance The resistance of an electrical component is R = V I (3) where V is the potential difference across the component, and I the electric current flowing through it. The SI unit of electrical resistance is R = [V ] [I ] = V = VA = 1Ω (ohm) (4) A according to German physicist Georg Simon Ohm ( ). Resistance is a function of temperature. For example, as the electric current through a filament increases, the filament warms, and the resistance of the filament increases.
12 Ohm s Law Ohm s Law Ohm s Law For a metallic conductor at constant temperature, the electric potential difference across the component is directly proportional to the electric current flowing through it. Ohm s Law For a metallic conductor at constant temperature, the electric potential difference V across the component is V = RI (5) where R is the resistance of the component, and I the electric current flowing through the component.
13 Ohm s Law Ohm s Law (cont.) The difference between metallic and nonmetallic conductors is that nonmetallic conductors have much less conduction electrons. As a result, Ohm s Law is valid at constant temperature also for nonmetallic conductors such as carbon, in which the electric current is carried by free electrons. Some components and materials obey Ohm s Law for a range of temperatures while some others do not. For example, the resistance of a ceramic resistor stays relatively constant even when the resistor warms (Ohmic behaviour), but the resistance of a filament increases as the electric current increases (nonohmic behaviour).
14 Ohm s Law 5.2 Resistivity Resistivity ρ of a Wire At constant temperature the resistivity of a metallic wire is ρ = R A L where R is the resistance of the metallic wire of length L, and A is the crosssectional area of the wire. (6) The unit of resistivity is ρ = [R][A] = Ωm (7) [l] The smaller the resistivity, the better the electrical conductivity of the material.
15 Ohm s Law 5.2 Factors That Affect Resistance Resistance and Resistivity At constant temperature the resistance of a metallic wire R is proportional to the length of the wire L, and inversely proportional to the crosssectional area A R = ρ L A (8) where the constant of proportionality ρ is called the resistivity of the material. From the equation above we see that the factors that affect the resistance of a wire are its crosssectional area A, length L, and resistivity of the metal ρ. If the temperature is not constant, the resistance may change with the temperature. In a required practical you should investigate one or more of the factors that affect resistance experimentally. The understanding will be tested in Paper 1 and Paper 3 questions.
16 Electric Power 5.2 Power Dissipation P in a Component All real components dissipate energy in a DC circuit. Consider a constant electric field #» E inside a resistor in a DC circuit. As the amount of electric charge q moves across a potential difference V in the resistor, the work done by the electric field on the charge carriers is W = V q. The power at which the electric field does work is thus P = W t = V q = V q t t = V I (9) where I is the electric current through the resistor. Because the electric current is constant, the power supplied by the field equals the power dissipated in the component. As a result, the power dissipation in the resistor is equally P = V I.
17 Electric Power 5.2 Electric Power P Electric Power The electric power of an electrical component is P = V I where V is the potential difference across the component, and I the current flowing through it. The SI unit of electric power is [P] = [V ][I ] = VA = 1W (watt). (10) The electric power gives the amount of energy consumed by the component in the circuit in one second. The electric power gives also the power at which a voltage source supplies energy to the electric circuit. The supplied power is P = V I = electric potential difference across the source current in circuit.
18 Electric Power 5.2 Electric Power P: Joule s Law For an ohmic component, the potential difference across the component is V = RI. Substituting into the electric power equation gives P = V I = (RI )I = I 2 R or, P = V I = V V R = V 2 R, where R is the resistance of the component. The equation is known as Joule s Law. Joule s Law An ohmic component of resistance R dissipates energy in a DC circuit at the power P = I 2 R = V 2 R where I is the current flowing through the component, and V the electric potential difference across the component.
19 Resistors in Series and in Parallel 5.2 Resistors in Series Resistors in Series When resistors are connected in series, the total resistance R total is the sum of the individual resistances R total = R 1 + R (11) In electronics literature the total resistance is often called the equivalent resistance. Adding resistors in series increases the total resistance. Two resistors in series doubles the total resistance, three threefolds, and so on (R total = R + R = 2R, R total = R + R + R = 3R).
20 Resistors in Series and in Parallel 5.2 Resistors in Parallel Resistors in Parallel When resistors are connected in parallel, the relation between the total resistance R total and individual resistances is 1 R total = 1 R R (12) Adding resistors in parallel decreases the total resistance. Two resistors in parallel reduces the total resistance to one half of the original, three to one third of the original, and so on.
21 Resistors in Series and in Parallel 5.2 Resistors in Parallel: Derivation R 3 I 3 R 2 I I 2 I R 1 I 1 Figure: By Kirchhoff s First Law the total electric current is I = I 1 + I 2 + I 3. From the Ohm s Law V (V = RI I = V /R) it follows that R total = V 1 R 1 + V 2 R 2 + V 3 R 3. Since the ends of the resistors are at the same potential, the electric potential difference across the system is V = V 2 = V 2 = V 3, The potential differences are cancelled, and 1 R total = 1 R R R 3.
22 Resistors in Series and in Parallel 5.2 Three Resistors in Parallel R 3 = 30Ω I 3 R 2 = 30Ω I I 2 I R 1 = 30Ω I 1 Figure: Three identical 30 Ω resistors are connected in parallel. From the equation 1 R total = 1 R R R 3 = 1 30Ω Ω Ω = 3 we get for the total resistance 30Ω R total = 30Ω = 10Ω, which 3 is one third of the resistance of a resistor.
Engineering Fundamentals and Problem Solving, 6e
Engineering Fundamentals and Problem Solving, 6e Chapter 17 Electrical Circuits Chapter Objectives Compute the equivalent resistance of resistors in series and in parallel Apply Ohm s law to a resistive
More informationElectricity & Magnetism
Electricity & Magnetism D.C. Circuits Marline Kurishingal Note : This chapter includes only D.C. In AS syllabus A.C is not included. Recap... Electrical Circuit Symbols : Draw and interpret circuit diagrams
More informationDirect Current Circuits. February 18, 2014 Physics for Scientists & Engineers 2, Chapter 26 1
Direct Current Circuits February 18, 2014 Physics for Scientists & Engineers 2, Chapter 26 1 Kirchhoff s Junction Rule! The sum of the currents entering a junction must equal the sum of the currents leaving
More informationPhysics 1214 Chapter 19: Current, Resistance, and DirectCurrent Circuits
Physics 1214 Chapter 19: Current, Resistance, and DirectCurrent Circuits 1 Current current: (also called electric current) is an motion of charge from one region of a conductor to another. Current When
More informationChapter 3: Electric Current And DirectCurrent Circuits
Chapter 3: Electric Current And DirectCurrent Circuits 3.1 Electric Conduction 3.1.1 Describe the microscopic model of current Mechanism of Electric Conduction in Metals Before applying electric field
More informationChapter 2. Engr228 Circuit Analysis. Dr Curtis Nelson
Chapter 2 Engr228 Circuit Analysis Dr Curtis Nelson Chapter 2 Objectives Understand symbols and behavior of the following circuit elements: Independent voltage and current sources; Dependent voltage and
More informationInsulators Nonmetals are very good insulators; their electrons are very tightly bonded and cannot move.
SESSION 11: ELECTRIC CIRCUITS Key Concepts Resistance and Ohm s laws Ohmic and nonohmic conductors Series and parallel connection Energy in an electric circuit Xplanation 1. CONDUCTORS AND INSULATORS
More informationChapter 16. Current and Drift Speed. Electric Current, cont. Current and Drift Speed, cont. Current and Drift Speed, final
Chapter 6 Current, esistance, and Direct Current Circuits Electric Current Whenever electric charges of like signs move, an electric current is said to exist The current is the rate at which the charge
More informationChapter 18 Electric Currents
Chapter 18 Electric Currents 1 The Electric Battery Volta discovered that electricity could be created if dissimilar metals were connected by a conductive solution called an electrolyte. This is a simple
More informationElectric Current. Chapter 17. Electric Current, cont QUICK QUIZ Current and Resistance. Sections: 1, 3, 4, 6, 7, 9
Electric Current Chapter 17 Current and Resistance Sections: 1, 3, 4, 6, 7, 9 Whenever electric charges of like signs move, an electric current is said to exist The current is the rate at which the charge
More informationLook over Chapter 26 sections 17 Examples 3, 7. Look over Chapter 18 sections 15, 8 over examples 1, 2, 5, 8, 9,
Look over Chapter 26 sections 17 Examples 3, 7 Look over Chapter 18 sections 15, 8 over examples 1, 2, 5, 8, 9, 1)How to find a current in a wire. 2)What the Current Density and Draft Speed are. 3)What
More informationPHYSICS FORM 5 ELECTRICAL QUANTITES
QUANTITY SYMBOL UNIT SYMBOL Current I Amperes A Voltage (P.D.) V Volts V Resistance R Ohm Ω Charge (electric) Q Coulomb C Power P Watt W Energy E Joule J Time T seconds s Quantity of a Charge, Q Q = It
More informationChapter 3: Electric Current and DirectCurrent Circuit
Chapter 3: Electric Current and DirectCurrent Circuit n this chapter, we are going to discuss both the microscopic aspect and macroscopic aspect of electric current. Directcurrent is current that flows
More informationA) Know that electric current is the rate of flow of charge 1 What is current?
PHYSICS AS UNIT 1 SECTION 3: CURRENT ELECTRiCiTY Question Answer A) Know that electric current is the rate of flow of charge 1 What is current? The rate of flow of charge Measured in amps (A) Symbol is
More informationLorik educational academyvidyanagar
Lorik educational academyvidyanagar 9849180367  Section: Senior TOPIC: CURRENT ELECTRICITY
More informationPhysics for Scientists & Engineers 2
Review The resistance R of a device is given by Physics for Scientists & Engineers 2 Spring Semester 2005 Lecture 8 R =! L A ρ is resistivity of the material from which the device is constructed L is the
More information10/14/2018. Current. Current. QuickCheck 30.3
Current If QCurrent is the total amount of charge that has moved past a point in a wire, we define the current I in the wire to be the rate of charge flow: The SI unit for current is the coulomb per second,
More informationChapter 27. Current And Resistance
Chapter 27 Current And Resistance Electric Current Electric current is the rate of flow of charge through some region of space The SI unit of current is the ampere (A) 1 A = 1 C / s The symbol for electric
More informationRevision checklist SP10. SP10 Electricity and Circuits. SP10a Electric circuits. SP10b Current and potential difference
Electricity and Circuits a Electric circuits Describe the basic structure of an atom (positions, relative masses and relative charges of protons, neutrons and electrons). Recognise the circuit symbols
More informationELECTRICAL THEORY. Ideal Basic Circuit Element
ELECTRICAL THEORY PROF. SIRIPONG POTISUK ELEC 106 Ideal Basic Circuit Element Has only two terminals which are points of connection to other circuit components Can be described mathematically in terms
More informationCHAPTER 1 ELECTRICITY
CHAPTER 1 ELECTRICITY Electric Current: The amount of charge flowing through a particular area in unit time. In other words, it is the rate of flow of electric charges. Electric Circuit: Electric circuit
More information2/25/2014. Circuits. Properties of a Current. Conservation of Current. Definition of a Current A. I A > I B > I C B. I B > I A C. I C D. I A E.
Circuits Topics: Current Conservation of current Batteries Resistance and resistivity Simple circuits 0.1 Electromotive Force and Current Conventional current is the hypothetical flow of positive charges
More information52 VOLTAGE, CURRENT, RESISTANCE, AND POWER
52 VOLTAGE, CURRENT, RESISTANCE, AND POWER 1. What is voltage, and what are its units? 2. What are some other possible terms for voltage? 3. Batteries create a potential difference. The potential/voltage
More informationAP Physics C. Electric Circuits III.C
AP Physics C Electric Circuits III.C III.C.1 Current, Resistance and Power The direction of conventional current Suppose the crosssectional area of the conductor changes. If a conductor has no current,
More informationTest Review Electricity
Name: Date: 1. An operating television set draws 0.71 ampere of current when connected to a 120volt outlet. Calculate the time it takes the television to consume 3.0 10 5 joules of electric energy. [Show
More informationCurrent and Resistance
Current and Resistance 1 Define the current. Understand the microscopic description of current. Discuss the rat at which the power transfer to a device in an electric current. 2 21 Electric current 22
More informationCurrent. Lecture 10. Chapter Physics II. Course website:
Lecture 10 Chapter 30 Physics II Current Course website: http://faculty.uml.edu/andriy_danylov/teaching/physicsii 95.144 Lecture Capture: http://echo360.uml.edu/danylov201415/physics2spring.html A Model
More informationChapter 26 DirectCurrent Circuits
Chapter 26 DirectCurrent Circuits 1 Resistors in Series and Parallel In this chapter we introduce the reduction of resistor networks into an equivalent resistor R eq. We also develop a method for analyzing
More informationChapter 17. Current and Resistance. Sections: 1, 3, 4, 6, 7, 9
Chapter 17 Current and Resistance Sections: 1, 3, 4, 6, 7, 9 Equations: 2 2 1 e r q q F = k 2 e o r Q k q F E = = I R V = A L R ρ = )] ( 1 [ o o T T + = α ρ ρ V I V t Q P = = R V R I P 2 2 ) ( = = C Q
More informationELECTRICITY. Prepared by: M. S. KumarSwamy, TGT(Maths) Page
ELECTRICITY 1. Name a device that helps to maintain a potential difference across a conductor. Cell or battery 2. Define 1 volt. Express it in terms of SI unit of work and charge calculate the amount of
More informationIntroduction to Electrical Theory and DC Circuits
Introduction to Electrical Theory and DC Circuits For Engineers of All Disciplines by James Doane, PhD, PE Contents 1.0 Course Overview... 4 2.0 Fundamental Concepts... 4 2.1 Electric Charges... 4 2.1.1
More informationNotes on Electricity (Circuits)
A circuit is defined to be a collection of energygivers (batteries) and energytakers (resistors, light bulbs, radios, etc.) that form a closed path (or complete path) through which electrical current
More informationSirindhorn International Institute of Technology Thammasat University at Rangsit
Sirindhorn International Institute of Technology Thammasat University at Rangsit School of Information, Computer and Communication Technology COURSE : ECS 304 Basic Electrical Engineering Lab INSTRUCTOR
More informationEXPERIMENT 12 OHM S LAW
EXPERIMENT 12 OHM S LAW INTRODUCTION: We will study electricity as a flow of electric charge, sometimes making analogies to the flow of water through a pipe. In order for electric charge to flow a complete
More informationChapter 26 DirectCurrent Circuits
Chapter 26 DirectCurrent Circuits 1 Resistors in Series and Parallel In this chapter we introduce the reduction of resistor networks into an equivalent resistor R eq. We also develop a method for analyzing
More informationphysics for you February 11 Page 68
urrent Electricity Passage 1 4. f the resistance of a 1 m length of a given wire t is observed that good conductors of heat are also is 8.13 10 3 W, and it carried a current 1, the good conductors of electricity.
More informationClass 8. Resistivity and Resistance Circuits. Physics 106. Winter Press CTRLL to view as a slide show. Class 8. Physics 106.
and Circuits and Winter 2018 Press CTRLL to view as a slide show. Last time we learned about Capacitance Problems ParallelPlate Capacitors Capacitors in Circuits Current Ohm s Law and Today we will learn
More informationRECALL?? Electricity concepts in Grade 9. Sources of electrical energy Current Voltage Resistance Power Circuits : Series and Parallel
Unit 3C Circuits RECALL?? Electricity concepts in Grade 9. Sources of electrical energy Current Voltage Resistance Power Circuits : Series and Parallel 2 Types of Electricity Electrostatics Electricity
More informationElectric Current & DC Circuits
Electric Current & DC Circuits Circuits Click on the topic to go to that section Conductors Resistivity and Resistance Circuit Diagrams Measurement EMF & Terminal Voltage Kirchhoff's Rules Capacitors*
More informationClicker Session Currents, DC Circuits
Clicker Session Currents, DC Circuits Wires A wire of resistance R is stretched uniformly (keeping its volume constant) until it is twice its original length. What happens to the resistance? 1) it decreases
More informationPhysics 102 Lab 4: Circuit Algebra and Effective Resistance Dr. Timothy C. Black Spring, 2005
Physics 02 Lab 4: Circuit Algebra and Effective Resistance Dr. Timothy C. Black Spring, 2005 Theoretical Discussion The Junction Rule: Since charge is conserved, charge is neither created or destroyed
More informationphysics 4/7/2016 Chapter 31 Lecture Chapter 31 Fundamentals of Circuits Chapter 31 Preview a strategic approach THIRD EDITION
Chapter 31 Lecture physics FOR SCIENTISTS AND ENGINEERS a strategic approach THIRD EDITION randall d. knight Chapter 31 Fundamentals of Circuits Chapter Goal: To understand the fundamental physical principles
More information1 Written and composed by: Prof. Muhammad Ali Malik (M. Phil. Physics), Govt. Degree College, Naushera
CURRENT ELECTRICITY Q # 1. What do you know about electric current? Ans. Electric Current The amount of electric charge that flows through a cross section of a conductor per unit time is known as electric
More informationES250: Electrical Science. HW1: Electric Circuit Variables, Elements and Kirchhoff s Laws
ES250: Electrical Science HW1: Electric Circuit Variables, Elements and Kirchhoff s Laws Introduction Engineers use electric circuits to solve problems that are important to modern society, such as: 1.
More informationElectric Currents and Circuits
Nicholas J. Giordano www.cengage.com/physics/giordano Chapter 19 Electric Currents and Circuits Marilyn Akins, PhD Broome Community College Electric Circuits The motion of charges leads to the idea of
More informationChapter 33  Electric Fields and Potential. Chapter 34  Electric Current
Chapter 33  Electric Fields and Potential Chapter 34  Electric Current Electric Force acts through a field An electric field surrounds every electric charge. It exerts a force that causes electric charges
More informationPhysics 7B1 (A/B) Professor Cebra. Winter 2010 Lecture 2. Simple Circuits. Slide 1 of 20
Physics 7B1 (A/B) Professor Cebra Winter 2010 Lecture 2 Simple Circuits Slide 1 of 20 Conservation of Energy Density In the First lecture, we started with energy conservation. We divided by volume (making
More informationCapacitance. A different kind of capacitor: Work must be done to charge a capacitor. Capacitors in circuits. Capacitor connected to a battery
Capacitance The ratio C = Q/V is a conductor s self capacitance Units of capacitance: Coulomb/Volt = Farad A capacitor is made of two conductors with equal but opposite charge Capacitance depends on shape
More informationCollege Physics B  PHY2054C
Power College  PHY2054C and 09/15/2014 My Office Hours: Tuesday 10:00 AM  Noon 206 Keen Building PHY2054C Power First MiniExam this week on Wednesday!! Location: UPL 101, 10:1011:00 AM Exam on chapters
More informationIntroductory Circuit Analysis
Introductory Circuit Analysis CHAPTER 6 Parallel dc Circuits OBJECTIVES Become familiar with the characteristics of a parallel network and how to solve for the voltage, current, and power to each element.
More informationElectric Currents and Circuits
Electric Currents and Circuits Producing Electric Current Electric Current flow of charged particles Need a potential difference to occur Conventional Current flow of positive charges flowing from positive
More informationBy Mir Mohammed Abbas II PCMB 'A' CHAPTER FORMULAS & NOTES. 1. Current through a given area of a conductor is the net charge passing
Formulae For u CURRENT ELECTRICITY 1 By Mir Mohammed Abbas II PCMB 'A' 1 Important Terms, Definitions & Formulae CHAPTER FORMULAS & NOTES 1. Current through a given area of a conductor is the net charge
More information5. ELECTRIC CURRENTS
5. ELECTRIC CURRENTS TOPIC OUTLINE Section Recommended Time Giancoli Section 5.1 Potential Difference, Current, Resistance 5.2 Electric Circuits 3h 19.1, 19.2 6.2 Electric Field and Force 6.3 Magnetic
More informationENGR 2405 Class No Electric Circuits I
ENGR 2405 Class No. 48056 Electric Circuits I Dr. R. Williams Ph.D. rube.williams@hccs.edu Electric Circuit An electric circuit is an interconnec9on of electrical elements Charge Charge is an electrical
More informationTopic 5.1 Electric Force and Field
Topic 5.1 Electric Force and Field Kari Eloranta 2016 Jyväskylän Lyseon lukio International Baccalaureate August 15, 2016 Electric Charge Electric Charge Q Electric charge Q Electric charge is the physical
More informationKirchhoff's Laws and Circuit Analysis (EC 2)
Kirchhoff's Laws and Circuit Analysis (EC ) Circuit analysis: solving for I and V at each element Linear circuits: involve resistors, capacitors, inductors Initial analysis uses only resistors Power sources,
More informationClosed loop of moving charges (electrons move  flow of negative charges; positive ions move  flow of positive charges. Nucleus not moving)
Unit 2: Electricity and Magnetism Lesson 3: Simple Circuits Electric circuits transfer energy. Electrical energy is converted into light, heat, sound, mechanical work, etc. The byproduct of any circuit
More informationLecture # 2 Basic Circuit Laws
CPEN 206 Linear Circuits Lecture # 2 Basic Circuit Laws Dr. Godfrey A. Mills Email: gmills@ug.edu.gh Phone: 026907363 February 5, 206 Course TA David S. Tamakloe CPEN 206 Lecture 2 205_206 What is Electrical
More informationTARGET STUDY MATERIAL
TARGET STUDY MATERIAL CBSE  X SCIENCE AND MATHS VOL I 1) PHYSICS  375 2) CHEMISTRY  79138 3) BIOLOGY  141214 4) MATHS  217325 TARGET EDUCATIONAL INSTITUTION Target Educational institution is the
More informationAC vs. DC Circuits. Constant voltage circuits. The voltage from an outlet is alternating voltage
Circuits AC vs. DC Circuits Constant voltage circuits Typically referred to as direct current or DC Computers, logic circuits, and battery operated devices are examples of DC circuits The voltage from
More information8. Electric circuit: The closed path along which electric current flows is called an electric circuit.
GIST OF THE LESSON 1. Positive and negative charges: The charge acquired by a glass rod when rubbed with silk is called positive charge and the charge acquired by an ebonite rod when rubbed with wool is
More informationDirect Current (DC) Circuits
Direct Current (DC) Circuits NOTE: There are short answer analysis questions in the Participation section the informal lab report. emember to include these answers in your lab notebook as they will be
More informationWhich of the following is the SI unit of gravitational field strength?
T52 [122 marks] 1. A cell is connected in series with a 2.0Ω resistor and a switch. The voltmeter is connected across the cell and reads 12V when the switch is open and 8.0V when the switch is closed.
More informationPhysics 1302W.400 Lecture 21 Introductory Physics for Scientists and Engineering II
Physics 1302W.400 Lecture 21 Introductory Physics for Scientists and Engineering II In today s lecture, we will learn to: Calculate the resistance of a conductor depending on the material and shape Apply
More informationElectric Current & DC Circuits How to Use this File Electric Current & DC Circuits Click on the topic to go to that section Circuits
Slide 1 / 127 Slide 2 / 127 Electric Current & DC Circuits www.njctl.org Slide 3 / 127 How to Use this File Slide 4 / 127 Electric Current & DC Circuits Each topic is composed of brief direct instruction
More informationCLASS X ELECTRICITY
Conductor Insulator: Materia Materials through which electric current cannot pass are called insulators. Electric Circuit: A continuous a CLASS X ELECTRICITY als through which electric current can pass
More informationA Review of Circuitry
1 A Review of Circuitry There is an attractive force between a positive and a negative charge. In order to separate these charges, a force at least equal to the attractive force must be applied to one
More informationCircuits Practice Websheet 18.1
Circuits Practice Websheet 18.1 Multiple Choice Identify the choice that best completes the statement or answers the question. 1. How much power is being dissipated by one of the 10Ω resistors? a. 24
More informationCan You Light the Bulb?
AP PHYSCS 2 Can You Light the Bulb? UNT 4 DC circuits and RC circuits. CHAPTER 16 DC CRCUTS 1. Draw wires and make the bulb light. 2. Modify your drawing and use ONE wire only! Complete circuits To check
More informationQ2 How many coulombs of charge leave the power supply during each second?
Part I  Circuit Elements in Series In Figure 1 at the right circuit elements #1, #2, #3 (in this case light bulbs) are said to be connected "IN SERIES". That is, they are connected in a series one right
More informationDirect Current (DC): In a DC circuit the current and voltage are constant as a function of time. Power (P): Rate of doing work P = dw/dt units = Watts
Lecture 1: Introduction Some Definitions: Current (I): Amount of electric charge (Q) moving past a point per unit time I dq/dt Coulombs/sec units Amps (1 Coulomb 6x10 18 electrons) oltage (): Work needed
More informationScience Olympiad Circuit Lab
Science Olympiad Circuit Lab Key Concepts Circuit Lab Overview Circuit Elements & Tools Basic Relationships (I, V, R, P) Resistor Network Configurations (Series & Parallel) Kirchhoff s Laws Examples Glossary
More informationM. C. Escher: Waterfall. 18/9/2015 [tsl425 1/29]
M. C. Escher: Waterfall 18/9/2015 [tsl425 1/29] Direct Current Circuit Consider a wire with resistance R = ρl/a connected to a battery. Resistor rule: In the direction of I across a resistor with resistance
More informationELECTRIC CURRENTS D R M A R T A S T A S I A K D E P A R T M E N T O F C Y T O B I O L O G Y A N D P R O T E O M I C S
ELECTRIC CURRENTS D R M A R T A S T A S I A K D E P A R T M E N T O F C Y T O B I O L O G Y A N D P R O T E O M I C S lecture based on 2016 Pearson Education, Ltd. The Electric Battery Electric Current
More informationElectricity. dronstudy.com
Electricity Electricity is a basic part of our nature and it is one of our most widely used forms of energy. We use electricity virtually every minute of every day for example in lighting, heating, refrigeration,
More information(b) State the relation between work, charge and potential difference for an electric circuit.
Question Bank on ChElectricity 1. (a) Define the S.I unit of potential difference. (b) State the relation between work, charge and potential difference for an electric circuit. Calculate the potential
More informationChapter 28. Direct Current Circuits
Chapter 28 Direct Current Circuits Electromotive Force An electromotive force device, or emf device, is a source of constant potential. The emf describes the work done per unit charge and has units of
More informationNotes on Electricity (Circuits)
A circuit is defined to be a collection of energygivers (active elements) and energytakers (passive elements) that form a closed path (or complete path) through which electrical current can flow. The
More informationFor an electric current to flow between two points, two conditions must be met.
ELECTROSTATICS LAB Electric Circuits For an electric current to flow between two points, two conditions must be met. 1. There must be a conducting path between the points along which the charges can move.
More informationChapter 25 Current, Resistance, and Electromotive Force
Chapter 25 Current, Resistance, and Electromotive Force Lecture by Dr. Hebin Li Goals for Chapter 25 To understand current and how charges move in a conductor To understand resistivity and conductivity
More informationLecture Outline Chapter 21. Physics, 4 th Edition James S. Walker. Copyright 2010 Pearson Education, Inc.
Lecture Outline Chapter 21 Physics, 4 th Edition James S. Walker Chapter 21 Electric Current and Direct Current Circuits Units of Chapter 21 Electric Current Resistance and Ohm s Law Energy and Power
More informationBasic Laws. Bởi: Sy Hien Dinh
Basic Laws Bởi: Sy Hien Dinh INTRODUCTION Chapter 1 introduced basic concepts such as current, voltage, and power in an electric circuit. To actually determine the values of this variable in a given circuit
More informationDynamic Electricity. All you need to be an inventor is a good imagination and a pile of junk. Thomas Edison
Dynamic Electricity All you need to be an inventor is a good imagination and a pile of junk. Thomas Edison Review Everything is made of atoms which contain POSITIVE particles called PROTONS and NEGATIVE
More informationINTRODUCTION TO ELECTRONICS
INTRODUCTION TO ELECTRONICS Basic Quantities Voltage (symbol V) is the measure of electrical potential difference. It is measured in units of Volts, abbreviated V. The example below shows several ways
More informationPhysics 212 Midterm 2 Form A
1. A wire contains a steady current of 2 A. The charge that passes a cross section in 2 s is: A. 3.2 1019 C B. 6.4 1019 C C. 1 C D. 2 C E. 4 C 2. In a Physics 212 lab, Jane measures the current versus
More informationSIMPLE D.C. CIRCUITS AND MEASUREMENTS Background
SIMPLE D.C. CICUITS AND MEASUEMENTSBackground This unit will discuss simple D.C. (direct current current in only one direction) circuits: The elements in them, the simple arrangements of these elements,
More informationVersion 001 CIRCUITS holland (1290) 1
Version CIRCUITS holland (9) This printout should have questions Multiplechoice questions may continue on the next column or page find all choices before answering AP M 99 MC points The power dissipated
More informationCOE. DC. Challenging MCQ questions by The Physics Cafe. Compiled and selected by The Physics Cafe
COE. DC Challenging MCQ questions by The Physics Cafe Compiled and selected by The Physics Cafe 1 battery of internal resistance r and e.m.f. E can supply a current of 6.0 to a resistor R as shown in Fig
More informationCircuits. Electric Current & DC Circuits. Slide 1 / 127. Slide 2 / 127. Slide 3 / 127. Slide 4 / 127. Slide 5 / 127. Slide 6 / 127
Slide 1 / 127 Slide 2 / 127 New Jersey Center for Teaching and Learning Electric Current & DC Circuits www.njctl.org Progressive Science Initiative This material is made freely available at www.njctl.org
More informationLesson 8 Electrical Properties of Materials. A. Definition: Current is defined as the rate at which charge flows through a surface:
Lesson 8 Electrical Properties of Materials I. Current I A. Definition: Current is defined as the rate at which charge flows through a surface: + + B. Direction: The direction of positive current flow
More informationLecture 11. Power in Electric Circuits, Kirchhoff s Rules
Lecture 11. Power in Electric Circuits, Kirchhoff s Rules Outline: Energy and power in electric circuits. Voltage and Current Sources. Kirchhoff s Rules. Lecture 10: Connection of resistors in parallel
More informationElectrical Circuits. Sources of Voltage
Electrical Circuits ALESSANDRO VOLTA (17451827) ANDRE MARIE AMPERE (17751836) GEORG SIMON OHM (17891854) POTENTIAL IN VOLTS, CURRENT IN AMPS, RESISTANCE IN OHMS! Sources of Voltage Voltage, also known
More informationELECTRICITY UNIT REVIEW
ELECTRICITY UNIT REVIEW S1304: How does the Atomic Model help to explain static electricity? 1. Which best describes static electricity? a) charges that can be collected and held in one place b) charges
More informationChapter 21 Electric Current and Direct Current Circuits
Chapter 21 Electric Current and Direct Current Circuits Units of Chapter 21 Electric Current Resistance and Ohm s Law Energy and Power in Electric Circuits Resistors in Series and Parallel Kirchhoff s
More informationThey keep the voltage the same and use this circuit to measure the current. Variable resistor. Reading on ammeter in amps
1 Ksenia and Eva investigate five different variable resistors. They set each variable resistor to the maximum resistance. They keep the voltage the same and use this circuit to measure the current. A
More informationDirect Current Circuits
Name: Date: PC1143 Physics III Direct Current Circuits 5 Laboratory Worksheet Part A: SingleLoop Circuits R 1 = I 0 = V 1 = R 2 = I 1 = V 2 = R 3 = I 2 = V 3 = R 12 = I 3 = V 12 = R 23 = V 23 = R 123
More informationChapter 20 Electric Circuits
Chapter 0 Electric Circuits Chevy olt  Electric vehicle of the future Goals for Chapter 9 To understand the concept of current. To study resistance and Ohm s Law. To observe examples of electromotive
More informationParallel Resistors (32.6)
Parallel Resistors (32.6) Resistors connected at both ends are called parallel resistors Neil Alberding (SFU Physics) Physics 121: Optics, Electricity & Magnetism Spring 2010 1 / 1 Parallel Resistors (32.6)
More informationElectric Currents. Resistors (Chapters 2728)
Electric Currents. Resistors (Chapters 2728) Electric current I Resistance R and resistors Relation between current and resistance: Ohm s Law Resistivity ρ Energy dissipated by current. Electric power
More informationPhysics 115. General Physics II. Session 24 Circuits Series and parallel R Meters Kirchoff s Rules
Physics 115 General Physics II Session 24 Circuits Series and parallel R Meters Kirchoff s Rules R. J. Wilkes Email: phy115a@u.washington.edu Home page: http://courses.washington.edu/phy115a/ 5/15/14 Phys
More information