Lecture 6. Previous Lecture. Capacitors C. Capacitors in series Capacitors in parallel E stored in an E field
|
|
- Franklin Griffith
- 5 years ago
- Views:
Transcription
1 Lecture 6 Previous Lecture Q Capacitors C V Capacitors in series Capacitors in parallel E stored in an E field 1 1 = = C C Δ series parallel This Lecture Current Resistivity as a property of materials Emf 1 C i i i = C 1 1 PEcap = QΔ V uelec = ε0e 2 2 i 2
2 Exam 1(Monday Feb. 4, 8:00-9:30 PM) *Location STEW 183 *Covers all readings, lectures, homework from Chapters 17 through 19.4 *The exam will be multiple choice and is meant to be done within 60 minutes by a well-prepared student. We will give 90 minutes starting promptly at the listed time, so please be on time! Be sure to bring your student ID card, calculator, pencil and your own onepage (two-side) crib sheet. NOTE THAT FEW EQUATIONS WILL BE GIVEN YOU ARE REMINDED THAT IT IS YOUR RESPONSIBILITY TO CREATE WHATEVER TWO-SIDED CRIB SHEET YOU WANT TO BRING TO THIS EXAM. 1/27/13 2
3 ILQ 1 Currently, Physics 221 help center is open on M and F only. Would you prefer to re-schedule the help center instructors from M and F to other days of the week (T, W, and Th)? The total number of available help hours per week would not change. A: YES, open the help center on (T, W, and Th), but reduce available hours on M and F. B: NO, keep the help center opened on M and F only. 3
4 Electrostatics versus Electric Current Conductors have free electrons moving at ~10 6 m/s. Electrons bump into the fixed positive nuclei random paths. On average no net displacement of charge no current 4
5 Electric Current Electrostatic Equilibrium Steady-State + - Battery Current is defined as the rate of flow of charge through an area. ΔQ I = Δt SI unit for I is the ampere (A). 1A = 1C s Convention: Current arrow is drawn in direction in which positive charge carriers would move, even if the actual charges are negative & move in the opposite direction. 5
6 Electric Current Notice that flow of positive charge in one direction, Becomes more negative Becomes more positive CURRENT I Equivalent to negative charge in opposite direction. Becomes more negative CURRENT I Becomes more positive
7 Drift Velocity In an electric field there is a drift along a preferred direction. With without E E Drift velocity = average speed of electrons DC Current: net flow through a surface 7
8 Drift Speed, Total Charge & Current # charge carriers n = volume q = charge of each particle v d = drift velocity In time Δt, all N particles in volume Av d Δt pass through area A: N = nav d Δt The total charge passing through A is: Q = qnav d Δt ΔQ Δt = qnav d = I 8
9 Relationship between Current and Drift Speed Find v d for 14-gauge copper wire carrying a current of 1 A. Assume there is 1 free electron/atom. Must find n =number of charged carriers/ V n = ρn M v d = I qna Copper ρ = 8.93 g/cm 3 M = g/mol 14 gauge wire A 2.081mm 2 9
10 Relationship between Current and Drift Speed Find v d for 14-gauge copper wire carrying a current of 1 A. Assume there is 1 free electron/atom. v d = I qna 19 Electrons are the carriers q= e= C C 1 I s vd = = qna ( C) ( m ) mm 6 v m d = = 35.4 µ m/s s Copper ρ = 8.93 g/cm 3 M = g/mol 14 gauge wire A 2.081mm 2 1 m 1000 mm An electron takes hours to travel 1 meter. 2 10
11 Electric Current one q in one q out A copper wire behaves like a full water hose. The wire is full of electrons. If the motion of charge starts at one end of the wire, then the other end reacts to this motion. This is like a full water hose Turn on the H 2 O pressure and water comes out immediately. The pressure wave travels much faster than an H 2 O molecule. 11
12 Resistance Resistance is a property of the object, i.e. It depends on the shape and material V =V a V b = E ΔL R = V I SI unit for resistance R : ohm (Ω) 1 Ω =1V / A Ohm s Law Ohmic materials (e.g., most metals): R is constant. Nonohmic materials: R constant 12
13 Resistance & Ohm s Law ohmic Non-ohmic 13
14 Resistivity Resistivity ( ρ) is a property of the material. area A I L I length R = ρ L A SI unit for ρ : ohm - meter (Ω m) Resistivity ρ depends on temperature. Usually the resistivity is given at T=20 o C. 14
15 ILQ 2 A metal rod has a length L, an area A, and an original resistance of R = 1Ω. The rod is then extruded to a final length 2L (and area A/2). What is the final resistance? (A) 1Ω (B) 2Ω (C) 4Ω 15
16 Resistivity & Temperature Coefficients Material Resistivity ρ (Ωm) Temp. coeff. α (K -1 ) Ag 1.6 x x 10-3 Cu 1.7 x x 10-3 W 5.5 x x 10-3 Si x 10-2 Si, n-type 8.7 x 10-4 Si, p-type 2.8 x 10-3 glass
17 Temperature Dependence ρ for copper (Cu) as a function of temperature Notice: Resisitivity increases as temperature increases. This curve does not deviate greatly from a straight line. 17
18 DEMO: Temperature Dependence liquid nitrogen ~ 77 o K Lower Cu initially at room temperature (~ 300 o K) into liquid N 2. vacuum bottle 18
19 DEMO: Temperature Dependence lamp B Heat the Ge with a candle. S semiconductor Ge 19
20 Real Battery internal resistance emf In an ideal battery: r = 0 V a V b = ε I = V R Examine potential as we start from point b and end at a: ε Ir IR = 0 I = Note: ε arrows always points from negative to positive. ε R + r Over the battery: V a V b = ε Ir 20
21 Effect of Internal Resistance r =0 (ideal battery) real battery 21
22 ILQ3 A human being can be electrocuted if a current as small as 50 ma passes near the heart. An electrician working with sweaty hands makes good contact with the two conductors that he is holding. If his resistance is 2000 Ω, which of the following might be the fatal voltage? (A) 100 V (B) (C) (D) 10 V 1 V 0.1 V (E) 0.01 V 22
23 Power P in electrical circuits When current flows through a resistance R, Joule heating occurs. ΔU = V ΔQ ΔU Δt = V ΔQ Δt = VI P = IV = I 2 R = V 2 R 23
9/22/16 ANNOUNCEMENT ANNOUNCEMENT FINAL EXAM
ANNOUNCEMENT Exam 1: Tuesday September 27, 2016, 8 PM 10 PM Location: Elliot Hall of Music Covers all readings, lectures, homework from Chapters 21 through 23 Multiple choice (1518 questions) Practice
More informationMonday July 14. Capacitance demo slide 19 Capacitors in series and parallel slide 33 Elmo example
Monday July 14 Lecture 5 Capacitance demo slide 19 Capacitors in series and parallel slide 33 Elmo example Lecture 6 Currents and esistance Lecture 9 Circuits Wear Microphone 1 3 Lecture 6 Current and
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 informationGeneral Physics (PHY 2140)
General Physics (PHY 2140) Lecture 7 Electrostatics and electrodynamics Capacitance and capacitors capacitors with dielectrics Electric current current and drift speed resistance and Ohm s law http://www.physics.wayne.edu/~apetrov/phy2140/
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 informationGeneral Physics (PHY 2140)
General Physics (PHY 2140) Lecture 4 Electrostatics and electrodynamics Capacitance and capacitors capacitors with dielectrics Electric current current and drift speed resistance and Ohm s law resistivity
More informationCurrent and Resistance. PHY2049: Chapter 26 1
Current and Resistance PHY2049: Chapter 26 1 What You Will Learn in This Chapter Nature of electric current Drift speed, current and current density Current and voltage measurements Conductivity and resistivity
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 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 informationPHYSICS. Chapter 27 Lecture FOR SCIENTISTS AND ENGINEERS A STRATEGIC APPROACH 4/E RANDALL D. KNIGHT
PHYSICS FOR SCIENTISTS AND ENGINEERS A STRATEGIC APPROACH 4/E Chapter 27 Lecture RANDALL D. KNIGHT Chapter 27 Current and Resistance IN THIS CHAPTER, you will learn how and why charge moves through a wire
More informationPhysics 202, Lecture 8. Exam 1
Physics 202, Lecture 8 Today s Topics More on Exam 1: logistics and mini-review Current And Resistance (Ch. 27) Current: Macroscopic and Microscopic Resistance: Macroscopic and Microscopic Electrical Power
More informationNote on Posted Slides. Flow of Charge. Electricity/Water Analogy: Continuing the Analogy. Electric Current
Note on Posted Slides These are the slides that I intended to show in class on Tue. Mar. 18, 2014. They contain important ideas and questions from your reading. Due to time constraints, I was probably
More informationCurrent and Resistance
Chapter 26 Current and Resistance Copyright 26-1 Electric Current As Fig. (a) reminds us, any isolated conducting loop regardless of whether it has an excess charge is all at the same potential. No electric
More information2 A bank account for electricity II: flows and taxes
PHYS 89 Lecture problems outline Feb 3, 204 Resistors and Circuits Having introduced capacitors, we now expand our focus to another very important component of a circuit resistors. This entails more interesting
More informationLook over Chapter 26 sections 1-7 Examples 3, 7. Look over Chapter 18 sections 1-5, 8 over examples 1, 2, 5, 8, 9,
Look over Chapter 26 sections 1-7 Examples 3, 7 Look over Chapter 18 sections 1-5, 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 informationElectric Current. You must know the definition of current, and be able to use it in solving problems.
Today s agenda: Electric Current. You must know the definition of current, and be able to use it in solving problems. Current Density. You must understand the difference between current and current density,
More informationAnnouncements. final exam average (excluding regrades): 79% regrade requests are due by Thursday, Sept 28 in recitation
Announcements final exam average (excluding regrades): 79% ill file. regrade requests are due by Thursday, Sept 28 in recitation On a separate sheet of paper, explain the reason for your request. This
More informationFlow Rate is the NET amount of water passing through a surface per unit time
Electric Current An Analogy Water Flow in a Pipe H 2 0 gallons/minute Flow Rate is the NET amount of water passing through a surface per unit time Individual molecules are bouncing around with speeds of
More informationChapter 27 Current and resistance
27.1 Electric Current Chapter 27 Current and resistance 27.2 Resistance 27.3 A Model for Electrical Conduction 27.4 Resistance and Temperature 27.6 Electrical Power 2 27.1 Electric Current Consider a system
More informationand in a simple circuit Part 2
Current, Resistance, and Voltage in a simple circuit Part 2 Electric Current Whenever electric charges of like signs move, an electric current is said to exist. Look at the charges flowing perpendicularly
More informationChapter 27. Current and Resistance
Chapter 27 Current and Resistance Electric Current Most practical applications of electricity deal with electric currents. The electric charges move through some region of space. The resistor is a new
More informationPhysics 202: Lecture 5, Pg 1
Resistance Resistors Series Parallel Ohm s law Electric Circuits Current Physics 132: Lecture e 15 Elements of Physics II Kirchhoff s laws Agenda for Today Physics 202: Lecture 5, Pg 1 Electric Current
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 informationUniversity Physics (PHY 2326)
Chapter 25 University Physics (PHY 2326) Lecture 7 Electrostatics and electrodynamics Capacitance and capacitors capacitors with dielectrics Electric current current and drift speed resistance and Ohm
More informationCurrent. source charges. test charg. 1. Charges in motion
Current 1. Charges in motion 1. Cause of motion 2. Where is it going? 3. Let's keep this going. 2. Current 1. Flow of particles in pipes. 2. A constant problem 3. Conservation Laws 4. Microscopic motion
More informationChapter 26 & 27. Electric Current and Direct- Current Circuits
Chapter 26 & 27 Electric Current and Direct- Current Circuits Electric Current and Direct- Current Circuits Current and Motion of Charges Resistance and Ohm s Law Energy in Electric Circuits Combination
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 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 informationPHYS 1444 Section 004 Lecture #10
PHYS 1444 Section 004 Lecture #10 Dr. Electric Current and Resistance The Battery Ohm s Law: Resisters Resistivity Electric Power Alternating Current Power Delivered by AC Today s homework is #6, due 10pm,
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 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 informationA free web support in Education. Internal resistance of the battery, r = 3 Ω. Maximum current drawn from the battery = I According to Ohm s law,
Exercises Question 3.1: The storage battery of a car has an emf of 12 V. If the internal resistance of the battery is 0.4Ω, what is the maximum current that can be drawn from the battery? Answer 3.1: Emf
More informationPHYSICS ASSIGNMENT ES/CE/MAG. Class XII
PHYSICS ASSIGNMENT ES/CE/MAG Class XII MM : 70 1. What is dielectric strength of a medium? Give its value for vacuum. 1 2. What is the physical importance of the line integral of an electrostatic field?
More informationLecture 6 Current and Resistance Ch. 26
Lecture 6 Current and esistance Ch. 6 Cartoon -nvention of the battery and Voltaic Cell Warm-up problem Topics What is current? Current density Conservation of Current esistance Temperature dependence
More informationChapter 27 Current and Resistance 27.1 Electric Current
Chapter 27 Current and esistance 27.1 Electric Current Electric current: dq dt, unit: ampere 1A = 1C s The rate at which charge flows through a surface. No longer have static equilibrium. E and Q can 0
More informationUnit 2. Current, Voltage and Resistance
Strand G. Electricity Unit 2. Current, Voltage and Resistance Contents Page Current 2 Potential Difference, Electromotive Force and Power 5 Resistance and Ohm s Law 9 G.2.1. Current In a metallic conductor
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 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 informationChapters 24/25: Current, Circuits & Ohm s law Thursday September 29 th **Register your iclickers**
Chapters 24/25: Current, Circuits & Ohm s law Thursday September 29 th **Register your iclickers** Conductors under dynamic conditions Current, current density, drift velocity Ohm s law Types of conductor
More informationPhysics 201. Professor P. Q. Hung. 311B, Physics Building. Physics 201 p. 1/3
Physics 201 p. 1/3 Physics 201 Professor P. Q. Hung 311B, Physics Building Physics 201 p. 2/3 Summary of last lecture Equipotential surfaces: Surfaces where the potential is the same everywhere, e.g. the
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 informationFXA 2008 ELECTRIC CHARGE (Q) 1. Candidates should be able to : Electric charge is a property possessed by protons and electrons.
ELECTRIC CHARGE (Q) 1 Candidates should be able to : Explain that electric current is a net flow of charged particles. Explain that electric current in a metal is due to the movement of electrons, whereas
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 informationElectricity
Electricity Electric Charge There are two fundamental charges in the universe. Positive (proton) has a charge of +1.60 x 10-19 C Negative (electron) has a charge of 1.60 x 10-19 C There is one general
More informationElectric Current. Electric current is the rate of flow of charge through some region of space The SI unit of current is the ampere (A)
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 current is I Average Electric
More informationPhysics 1502: Lecture 8 Today s Agenda. Today s Topic :
Physics 1502: Lecture 8 Today s Agenda Announcements: Lectures posted on: www.phys.uconn.edu/~rcote/ HW assignments, solutions etc. Homework #3: On Masterphysics today: due next Friday Go to masteringphysics.com
More informationChapter 27. Current and Resistance
Chapter 27 Current and Resistance Electric Current Most practical applications of electricity deal with electric currents. The electric charges move through some region of space. The resistor is a new
More informationELECTRIC CURRENT. Ions CHAPTER Electrons. ELECTRIC CURRENT and DIRECT-CURRENT CIRCUITS
LCTRC CURRNT CHAPTR 25 LCTRC CURRNT and DRCTCURRNT CRCUTS Current as the motion of charges The Ampère Resistance and Ohm s Law Ohmic and nonohmic materials lectrical energy and power ons lectrons nside
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 cross-sectional area of the conductor changes. If a conductor has no current,
More informationReview. Spring Semester /21/14. Physics for Scientists & Engineers 2 1
Review Spring Semester 2014 Physics for Scientists & Engineers 2 1 Notes! Homework set 13 extended to Tuesday, 4/22! Remember to fill out SIRS form: https://sirsonline.msu.edu Physics for Scientists &
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 informationChapter 3: Electric Current And Direct-Current Circuits
Chapter 3: Electric Current And Direct-Current 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 informationLouisiana State University Physics 2102, Exam 3, November 11, 2010.
Name: Instructor: Louisiana State University Physics 2102, Exam 3, November 11, 2010. Please be sure to write your name and class instructor above. The test consists of 3 questions (multiple choice), and
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 informationMP ) 12:40-2:40 3:00-4:00 PM
PHY294H l Professor: Joey Huston l email:huston@msu.edu l office: BPS3230 l Homework will be with Mastering Physics (and an average of 1 handwritten problem per week) Problem 29.77 (already assigned) will
More informationDr. Todd Satogata (ODU/Jefferson Lab) Wednesday, February
University Physics 227N/232N Capacitors, Field Energy, Current and Ohm s Law Lab deferred to Fri Feb 28 QUIZ this Friday! (Feb 21) Fred lectures Monday! (Feb 24) Dr. Todd Satogata (ODU/Jefferson Lab) satogata@jlab.org
More informationLesson 3. Electric Potential. Capacitors Current Electricity
Electric Potential Lesson 3 Potential Differences in a Uniform Electric Field Electric Potential and Potential Energy The Millikan Oil-Drop Experiment Capacitors Current Electricity Ohm s Laws Resistance
More informationElectric currents (primarily, in metals)
Electric currents (primarily, in metals) Benjamin Franklin was experimenting electricity in the mid- XVIII Century. Nobody knew if it was the positive charges or negative charges carrying the current through
More informationNews. Charge and Potential. Charge Density. Charge and Potential Quiz #2: Monday, 3/14, 10AM Same procedure as for quiz R +
News Charge and Potential Quiz #2: Monday, 3/14, 10AM Same procedure as for quiz 1 Review in class Fri, 3/11 Evening review, Fri, 3/11, 68PM 2 practice quizzes ( practice problems) Formula sheet R Charged
More informationChapter 25 Electric Currents and. Copyright 2009 Pearson Education, Inc.
Chapter 25 Electric Currents and Resistance 25-1 The Electric Battery Volta discovered that electricity could be created if dissimilar metals were connected by a conductive solution called an electrolyte.
More informationChapter 18. Direct Current Circuits
Chapter 18 Direct Current Circuits Sources of emf The source that maintains the current in a closed circuit is called a source of emf Any devices that increase the potential energy of charges circulating
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 informationPHYS 1444 Section 002 Lecture #13
PHYS 1444 Section 002 Lecture #13 Monday, Oct. 16, 2017 Dr. Animesh Chatterjee (disguising as Dr. Yu) Chapter 25 Electric Current Ohm s Law: Resisters, Resistivity Electric Power Alternating Current Microscopic
More informationCalculus Relationships in AP Physics C: Electricity and Magnetism
C: Electricity This chapter focuses on some of the quantitative skills that are important in your C: Mechanics course. These are not all of the skills that you will learn, practice, and apply during the
More informationLecture 14 Current Density Ohm s Law in Differential Form
Lecture 14 Current Density Ohm s Law in Differential Form Sections: 5.1, 5.2, 5.3 Homework: See homework file Direct Electric Current Review DC is the flow of charge under electrostatic forces in conductors
More informationPhysics 1202: Lecture 4 Today s Agenda. Today s Topic :
Physics 1202: Lecture 4 Today s Agenda Announcements: Lectures posted on: www.phys.uconn.edu/~rcote/ HW assignments, solutions etc. Homework #1: On Masterphysics: due this coming Friday Go to the syllabus
More informationIMPORTANT Read these directions carefully:
Physics 208: Electricity and Magnetism Common Exam 2, October 17 th 2016 Print your name neatly: First name: Last name: Sign your name: Please fill in your Student ID number (UIN): _ - - Your classroom
More informationChapter 17. Current and Resistance
Chapter 17 Current and Resistance Electric Current The current is the rate at which the charge flows through a surface Look at the charges flowing perpendicularly through a surface of area A I av The SI
More informationChapter 3: Current and Resistance. Direct Current Circuits
Chapter 3: Current and Resistance. Direct Current Circuits 3.1. Electric Current 3.2. Resistance and Resistivity 3.3. Ohm s Law and a Microscopic View of Ohm s Law 3.4. Semiconductors and Superconductors
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 informationPhysics 2102 Lecture 18: WED 08 OCT
Resistance Is Futile! Physics 2113 Jonathan Dowling Physics 2102 Lecture 18: WED 08 OCT Current & Resistance II Georg Simon Ohm (1789-1854) Resistance is NOT Futile! Electrons are not completely free to
More information3 Electric current, resistance, energy and power
3 3.1 Introduction Having looked at static charges, we will now look at moving charges in the form of electric current. We will examine how current passes through conductors and the nature of resistance
More informationELECTRICAL Quantities
1 ELECTRICAL Quantities Friction And Charge When two materials rub together the contact between their surfaces may cause: a) the surfaces to become hot and show wear and tear. b) the surfaces to become
More informationAP Physics C - E & M
AP Physics C - E & M Current and Circuits 2017-07-12 www.njctl.org Electric Current Resistance and Resistivity Electromotive Force (EMF) Energy and Power Resistors in Series and in Parallel Kirchoff's
More informationElectric Currents & Resistance
Electric Currents & Resistance Electric Battery A battery produces electricity by transforming chemical energy into electrical energy. The simplest battery contains two plates or rods made of dissimilar
More informationConceptual Physical Science 6 th Edition
Conceptual Physical Science 6 th Edition Chapter 8: STATIC AND CURRENT ELECTRICITY 1 Chapter 8: STATIC AND CURRENT ELECTRICITY Chapter 8: Read: All Homework: Four problems from the following set: 4, 6,
More informationLecture 7.1 : Current and Resistance
Lecture 7.1 : Current and Resistance Lecture Outline: Current and Current Density Conductivity and Resistivity Resistance and Ohm s Law Textbook Reading: Ch. 30.3-30.5 Feb. 26, 2013 1 Announcements By
More informationAlgebra Based Physics
Page 1 of 105 Algebra Based Physics Electric Current & DC Circuits 2015-10-06 www.njctl.org Page 2 of 105 Electric Current & DC Circuits Circuits Conductors Resistivity and Resistance Circuit Diagrams
More informationQuestion 3: How is the electric potential difference between the two points defined? State its S.I. unit.
EXERCISE (8 A) Question : Define the term current and state its S.I unit. Solution : Current is defined as the rate of flow of charge. I = Q/t Its S.I. unit is Ampere. Question 2: Define the term electric
More informationEXAM REVIEW ON MONDAY
EXAM REVIEW ON MONDAY 6:5 8:5 PM McCarty A Room G86 By JJ Stankowicz Also, formula sheet has been posted. PHY049: Chapter 5 Capacitance calculation review +q q Why do we always consider only +q and q pairs?
More informationChapter 25: Electric Current
Chapter 25: Electric Current Conductors and Charge Carriers Consider a conducting piece of metal: The valence electrons are weakly bound to the nuclei form a fluidlike sea of electrons that can move through
More informationDirect Currents. We will now start to consider charges that are moving through a circuit, currents. Sunday, February 16, 2014
Direct Currents We will now start to consider charges that are moving through a circuit, currents. 1 Direct Current Current usually consists of mobile electrons traveling in conducting materials Direct
More informationContinuing the Analogy. Electricity/Water Analogy: PHY205H1F Summer Physics of Everyday Life Class 8: Electric Current, Magnetism
PHY205H1F ummer Physics of Everyday Life Class 8: Electric Current, Magnetism Flow of Charge Voltage, Current, Resistance Ohm s Law DC and AC Electric Power Light bulbs Electric Circuits Magnetic Force
More informationFrom last time. Today: More on electric potential and connection to E-field How to calculate E-field from V Capacitors and Capacitance
From last time More on electric potential and connection to Efield How to calculate Efield from V Capacitors and Capacitance Today: More on Capacitors and Capacitance Energy stored in Capacitors Current
More informationPHYS 1442 Section 001. Lecture #5. Chapter 18. Wednesday, June 17, 2009 Dr. Jaehoon Yu
PHYS 1442 Section 001 Chapter 18 Lecture #5 Dr. The Electric Battery Ohm s Law: Resisters Resistivity Electric Power Alternating Current Power Delivered by AC Today s homework is #3, due 9pm, Thursday,
More informationWhat are the two types of current? The two types of current are direct current and alternating current.
Electric Current What are the two types of current? The two types of current are direct current and alternating current. Electric Current The continuous flow of electric charge is an electric current.
More informationV R I = UNIT V: Electricity and Magnetism Chapters Chapter 34: Electric Current. volt ohm. voltage. current = I. The Flow of Charge (34.
IMPORTANT TERMS: Alternating current (AC) Ampere Diode Direct current (DC) Electric current Electric power Electric resistance Ohm Ohm s Law Potential difference Voltage source EQUATIONS: UNIT V: Electricity
More informationElectric Currents and Simple Circuits
-1 Electric Currents and Simple Circuits Electrons can flow along inside a metal wire if there is an E-field present to push them along ( F= qe). The flow of electrons in a wire is similar to the flow
More informationPhys102 Second Major-161 Zero Version Coordinator: Dr. Naqvi Monday, December 12, 2016 Page: 1
Coordinator: Dr. Naqvi Monday, December 12, 2016 Page: 1 Q1. Two point charges, with charges q1 and q2, are placed a distance r apart. Which of the following statements is TRUE if the electric field due
More informationChapter.16 / Section.1: Electric Charge. Q=Ne Total Charge=number of electrons transferred fundamental charge
Revision Sheet for the Final Exam Academic Year: 2018/2019 First Term Subject: Physics Grade: 12 Student s name:. Date: 26/11/2017 Required Material: Chapter 16: Electric Forces and Fields, Sections: (1,
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 informationPhysics 1B Electricity & Magnetism. Frank Wuerthwein (Prof) Edward Ronan (TA) UCSD
Physics 1B Electricity & Magnetism Frank Wuerthwein (Prof) Edward Ronan (TA) UCSD Quiz 1 Quiz 1A and it s answer key is online at course web site. http://hepuser.ucsd.edu/twiki2/bin/view/ UCSDTier2/Physics1BWinter2012
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 Mini-Exam this week on Wednesday!! Location: UPL 101, 10:10-11:00 AM Exam on chapters
More informationELECTRICITY. Electric Circuit. What do you already know about it? Do Smarty Demo 5/30/2010. Electric Current. Voltage? Resistance? Current?
ELECTRICITY What do you already know about it? Voltage? Resistance? Current? Do Smarty Demo 1 Electric Circuit A path over which electrons travel, out through the negative terminal, through the conductor,
More informationChapter 26 Current and Resistance
Chapter 26 Current and Resistance Electric Current Although an electric current is a stream of moving charges, not all moving charges constitute an electric current. If there is to be an electric current
More informationElectricity & Magnetism Study Questions for the Spring 2018 Department Exam December 4, 2017
Electricity & Magnetism Study Questions for the Spring 2018 Department Exam December 4, 2017 1. a. Find the capacitance of a spherical capacitor with inner radius l i and outer radius l 0 filled with dielectric
More informationPhysics 220: Worksheet 7
(1 A resistor R 1 =10 is connected in series with a resistor R 2 =100. A current I=0.1 A is present through the circuit. What is the power radiated in each resistor and also in the total circuit? (2 A
More informationChapter 20: Electric Current, Resistance & Ohm s Law. Brent Royuk Phys-112 Concordia University
Chapter 20: Electric Current, Resistance & Ohm s Law Brent Royuk Phys-112 Concordia University The Minds of Our Own Challenge Light a bulb with a battery and a wire. Could you do it? 2 Introduction Batteries
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 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 information