n Higher Physics 1B (Special) (PHYS1241) (6UOC) n Advanced Science n Double Degree (Science/Engineering) n Credit or higher in Physics 1A
|
|
- Franklin Wilson
- 5 years ago
- Views:
Transcription
1 Physics in Session 2: I n Physics / Higher Physics 1B (PHYS1221/1231) n Science, dvanced Science n Engineering: Electrical, Photovoltaic,Telecom n Double Degree: Science/Engineering n 6 UOC n Waves n Physical Optics (light & interference) n Introduction to Quantum Physics n Solid State & Semiconductor Physics Physics in Session 2: II n Higher Physics 1B (Special) (PHYS1241) (6UOC) n dvanced Science n Double Degree (Science/Engineering) n Credit or higher in Physics 1 n Waves: interference, diffraction, polarization n Introduction to Quantum Mechanics n lternating Currents n The Sun and the Planets n Thermal Physics n Special Relativity Much smaller classes! Physics in Session 2: II n Energy & Environmental Physics n PHYS1211 (6UOC) / PHYS1249 (3UOC) n possible elective course? n Heat & Energy n Solar energy, alternative energy n Introductory quantum theory n Photovoltaic energy n Nuclear energy & radiation Physics / Higher Physics 1 Topic 3 Electricity and Magnetism Revision Electric Charges n Two kinds of electric charges n Called positive and negative n Like charges repel n Unlike charges attract Coulomb s Law n In vector form, F 12 =k e q 1 q 2 ˆ r r 2 n r ˆ is a unit vector directed from q 1 to q 2 n Like charges produce a repulsive force between them 1
2 The Superposition Principle n The resultant force on q 1 is the vector sum of all the forces exerted on it by other charges: F 1 = F 21 + F 31 + F 41 + Electric Field E F q e = = o q ke r r ˆ 2 n Continuous charge distribution q dq E = k lim rˆ = k rˆ i e 0 2 i e q 2 i i ri r Electric Field Lines Dipole n The charges are equal and opposite n The number of field lines leaving the positive charge equals the number of lines terminating on the negative charge Electric Flux Φ E =E i i cosθ i = E i i E Φ = lim E = d E i 0 i i surface Gauss s Law Φ E = E d = q in ε0 n q in is the net charge inside the surface n E represents the electric field at any point on the surface Field Due to a Plane of Charge n The total charge in the surface is σ n pplying Gauss s law Φ E = 2E = σ, and E = σ ε 0 2ε 0 n Field uniform everywhere 2
3 Properties of a Conductor in Electrostatic Equilibrium 1. Electric field is zero everywhere inside conductor 2. Charge resides on its surface of isolated conductor 3. Electric field just outside a charged conductor is perpendicular to the surface with magnitude σ /ε o 4. On an irregularly shaped conductor surface charge density is greatest where radius of curvature is smallest Electric Potential Energy n Work done by electric field is F. ds = q o E. ds n Potential energy of the charge-field system is changed by U = -q o E. ds n For a finite displacement of the charge from to B, the change in potential energy is U = U U = q E d s B o B Electric Potential, V n The potential energy per unit charge, U/q o, is the electric potential U B V = = d q E s o n The work performed on the charge is W = U = q V n In a uniform field B B V V = V = E ds = E ds = Ed B Equipotential Surface n ny surface consisting of a continuous distribution of points having the same electric potential n For a point charge q V = ke r Finding E From V n From V = -E.ds = -E x dx dv Ex = dx n long an equipotential surfaces V = 0 n Hence E ds n i.e. an equipotential surface is perpendicular to the electric field lines passing through it V Due to a Charged Conductor n E ds = 0 n So, potential difference between and B is zero n Electric field is zero inside the conductor n So, electric potential constant everywhere inside conductor and equal to value at the surface 3
4 Cavity in a Conductor n ssume an irregularly shaped cavity is inside a conductor n ssume no charges are inside the cavity n The electric field inside the conductor must be zero Definition of Capacitance n The capacitance, C, is ratio of the charge on either conductor to the potential difference between the conductors Q C = V n measure of the ability to store charge n The SI unit of capacitance is the farad (F) Capacitance Parallel Plates n Charge density σ = Q/ n Electric field E = σ/ε 0 (for conductor) n Uniform between plates, zero elsewhere C = Q V = Q Ed = Q ε = 0 Q ε 0 d d Capacitors in Parallel n Capacitors can be replaced with one capacitor with a capacitance of C eq n C eq = C 1 + C 2 Capacitors in Series n Potential differences add up to the battery voltage Q =Q 1 =Q 2 V = V 1 + V 2 V Q = V 1 Q 1 + V 2 Q 2 1 C = 1 C C 2 Energy of Capacitor n Work done in charging the capacitor appears as electric potential energy U: 2 Q 1 1 ( ) 2 U = = Q V = C V 2C 2 2 n Energy is stored in the electric field n Energy density (energy per unit volume) u E = U/Vol. = ½ ε o E 2 4
5 Capacitors with Dielectrics n dielectric is a nonconducting material that, when placed between the plates of a capacitor, increases the capacitance n For a parallel-plate capacitor C = κ C o = κ ε o (/d) Rewiring charged capacitors n Two capacitors, C 1 & C 2 charged to same potential difference, V i. n Capacitors removed from battery and plates connected with opposite polarity. n Switches S 1 & S 2 then closed. What is final potential difference, V f? Q 1i, Q 2i before; Q 1f, Q 2f after. Q 1i = C 1 V i ; Q 2i = -C 2 V i So Q=Q 1i +Q 2i =(C 1 -C 2 ) V i But Q= Q 1f +Q 2f (charge conserved) With Q 1f = C 1 V f ; Q 2f = C 2 V f hence Q 1f = C 1 /C 2 Q 2f So, Q=(C 1 /C 2 +1) Q 2f With some algebra, find Q 1f = QC 1 /(C 1 +C 2 ) & Q 2f = QC 2 /(C 1 +C 2 ) So V 1f = Q 1f / C 1 = Q / (C 1 +C 2 ) & V 2f = Q 2f / C 2 = Q / (C 1 +C 2 ) i.e. V 1f = V 2f = V f, as expected So V f = (C 1 - C 2 ) / (C 1 + C 2 ) V i, on substituting for Q Magnetic Poles n Every magnet has two poles n Called north and south poles n Poles exert forces on one another n Like poles repel n N-N or S-S n Unlike poles attract n N-S Magnetic Field Lines for a Bar Magnet n Compass can be used to trace the field lines n The lines outside the magnet point from the North pole to the South pole Direction n F B perpendicular to plane formed by v & B n Oppositely directed forces are exerted on charges of different signs n cause the particles to move in opposite directions 5
6 Direction given by Right-Hand Rule n Fingers point in the direction of v n (for positive charge; opposite direction if negative) n Curl fingers in the direction of B n Then thumb points in the direction of v x B; i.e. the direction of F B The Magnitude of F n The magnitude of the magnetic force on a charged particle is F B = q vb sin θ n θ is the angle between v and B n F B is zero when v and B are parallel n F B is a maximum when perpendicular Force on a Wire n F = I L x B n L is a vector that points in the direction of the current (i.e. of v D ) n Magnitude is the length L of the segment ni is the current = nqv D n B is the magnetic field Force on a Wire of rbitrary Shape n The force exerted segment ds is F = I ds x B n The total force is b d a F = I s B Force on Charged Particle n Equating the magnetic & centripetal forces: F =qvb = mv 2 r n Solving gives r = mv/qb Biot-Savart Law n db is the field created by the current in the length segment ds n Sum up contributions from all current elements I.ds B = µ 0 4π I ds ˆ r r 2 6
7 B for a Long, Straight Conductor B = µ 0 I 2πa B for a Long, Straight Conductor, Direction n Magnetic field lines are circles concentric with the wire n Field lines lie in planes perpendicular to to wire n Magnitude of B is constant on any circle of radius a n The right-hand rule for determining the direction of B is shown n Grasp wire with thumb in direction of current. Fingers wrap in direction of B. Magnetic Force Between Two Parallel Conductors F 1 = µ 0 I 1 I 2 2πa l n Parallel conductors carrying currents in the same direction attract each other n Parallel conductors carrying currents in opposite directions repel each other Definition of the mpere n The force between two parallel wires can be used to define the ampere F 1 l = µ 0 I 1 I 2 2πa with µ 0 = 4π 10 7 T m -1 n When the magnitude of the force per unit length between two long parallel wires that carry identical currents and are separated by 1 m is 2 x 10-7 N/m, the current in each wire is defined to be 1 mpere s Law n The line integral of B. ds around any closed path equals µ o I, where I is the total steady current passing through any surface bounded by the closed path. B ds = µ 0 I Field in interior of a Solenoid n pply mpere s law n The side of length l inside the solenoid contributes to the field n Path 1 in the diagram B ds = B ds = B ds = Bl path1 path 1 B = µ 0 N l I = µ 0 ni 7
8 mpere s vs. Gauss s Law B ds = µ 0 I E d = q ε 0 n Integrals around closed path vs. closed surface. n i.e. 2D vs. 3D geometrical figures n Integrals related to fundamental constant x source of the field. n Concept of Flux the flow of field lines through a surface. Gauss Law in Magnetism n Magnetic fields do not begin or end at any point n i.e. they form closed loops, with the number of lines entering a surface equaling the number of lines leaving that surface n Gauss law in magnetism says: Φ B = B.d = 0 Faraday s Law of Induction n The emf induced in a circuit is directly proportional to the rate of change of the magnetic flux through that circuit ε = N dφ B dt QuickTime and a Cinepak decompressor are needed to see this picture. Ways of Inducing an emf ε = d dt ( Bcosθ) n Magnitude of B can change with time n rea enclosed,, can change with time n ngle θ can change with time n ny combination of the above can occur Motional emf n Motional emf induced in a conductor moving through a constant magnetic field n Electrons in conductor experience a force, F B = qv x B that is directed along l n In equilibrium, qe = qvb or E = vb Sliding Conducting Bar n Magnetic flux is n The induced emf is ε = dφ B = d ( Blx)= Bl dx dt dt dt = Blv n Thus the current is I = ε R =Blv R Φ B =Blx 8
9 Induced emf & Electric Fields n changing magnetic flux induces an emf and a current in a conducting loop n n electric field is created in a conductor by a changing magnetic flux n Faraday s law can be written in a general form: ε = E.ds = dφ B dt n Not an electrostatic field because the line integral of E. ds is not zero. Generators n Electric generators take in energy by work and transfer it out by electrical transmission n The C generator consists of a loop of wire rotated by some external means in a magnetic field Rotating Loop n ssume a loop with N turns, all of the same area, rotating in a magnetic field n The flux through one loop at any time t is: Φ B = B cos θ = B cos ωt Motors n Motors are devices into which energy is transferred by electrical transmission while energy is transferred out by work n motor is a generator operating in reverse n current is supplied to the coil by a battery and the torque acting on the current-carrying coil causes it to rotate ε = N dφ B dt = NB d ( cosωt)=nbω sinωt dt Eddy Currents n Circulating currents called eddy currents are induced in bulk pieces of metal moving through a magnetic field n From Lenz s law, their direction is to oppose the change that causes them. n The eddy currents are in opposite directions as the plate enters or leaves the field Equations for Self-Inductance n Induced emf proportional to the rate of change of the current ε L = L di dt n L is a constant of proportionality called the inductance of the coil. 9
10 Inductance of a Solenoid n Uniformly wound solenoid having N turns and length l. Then we have: B = µ 0 ni = µ 0 N l I N Φ B =B = µ 0 I l L = NΦ B I = µ 0N 2 l Energy in a Magnetic Field n Rate at which the energy is stored is du di = LI dt dt I U =L IdI = 1 2 LI 2 0 n Magnetic energy density, u B, is u B = U l = B2 2µ 0 RL Circuit I = ε R 1 e Rt L = ε R 1 e t τ n Time constant, τ = L / R, for the circuit n τ is the time required for current to reach 63.2% of its max value 10
Physics / Higher Physics 1A. Electricity and Magnetism Revision
Physics / Higher Physics 1A Electricity and Magnetism Revision Electric Charges Two kinds of electric charges Called positive and negative Like charges repel Unlike charges attract Coulomb s Law In vector
More informationSliding Conducting Bar
Motional emf, final For equilibrium, qe = qvb or E = vb A potential difference is maintained between the ends of the conductor as long as the conductor continues to move through the uniform magnetic field
More informationChapter 30. Sources of the Magnetic Field Amperes and Biot-Savart Laws
Chapter 30 Sources of the Magnetic Field Amperes and Biot-Savart Laws F B on a Charge Moving in a Magnetic Field Magnitude proportional to charge and speed of the particle Direction depends on the velocity
More informationWhere k = 1. The electric field produced by a point charge is given by
Ch 21 review: 1. Electric charge: Electric charge is a property of a matter. There are two kinds of charges, positive and negative. Charges of the same sign repel each other. Charges of opposite sign attract.
More informationSUMMARY Phys 2523 (University Physics II) Compiled by Prof. Erickson. F e (r )=q E(r ) dq r 2 ˆr = k e E = V. V (r )=k e r = k q i. r i r.
SUMMARY Phys 53 (University Physics II) Compiled by Prof. Erickson q 1 q Coulomb s Law: F 1 = k e r ˆr where k e = 1 4π =8.9875 10 9 N m /C, and =8.85 10 1 C /(N m )isthepermittivity of free space. Generally,
More informationPhysics 202, Lecture 13. Today s Topics. Magnetic Forces: Hall Effect (Ch. 27.8)
Physics 202, Lecture 13 Today s Topics Magnetic Forces: Hall Effect (Ch. 27.8) Sources of the Magnetic Field (Ch. 28) B field of infinite wire Force between parallel wires Biot-Savart Law Examples: ring,
More informationElectrics. Electromagnetism
Electrics Electromagnetism Electromagnetism Magnetism is associated with charges in motion (currents): microscopic currents in the atoms of magnetic materials. macroscopic currents in the windings of an
More informationLouisiana State University Physics 2102, Exam 3 April 2nd, 2009.
PRINT Your Name: Instructor: Louisiana State University Physics 2102, Exam 3 April 2nd, 2009. Please be sure to PRINT your name and class instructor above. The test consists of 4 questions (multiple choice),
More informationPhysics 208, Spring 2016 Exam #3
Physics 208, Spring 206 Exam #3 A Name (Last, First): ID #: Section #: You have 75 minutes to complete the exam. Formulae are provided on an attached sheet. You may NOT use any other formula sheet. You
More informationPHY102 Electricity Course Summary
TOPIC 1 ELECTOSTTICS PHY1 Electricity Course Summary Coulomb s Law The magnitude of the force between two point charges is directly proportional to the product of the charges and inversely proportional
More informationMagnetism is associated with charges in motion (currents):
Electrics Electromagnetism Electromagnetism Magnetism is associated with charges in motion (currents): microscopic currents in the atoms of magnetic materials. macroscopic currents in the windings of an
More informationChapter 31. Faraday s Law
Chapter 31 Faraday s Law 1 Ampere s law Magnetic field is produced by time variation of electric field dφ B ( I I ) E d s = µ o + d = µ o I+ µ oεo ds E B 2 Induction A loop of wire is connected to a sensitive
More informationChapter 24. Magnetic Fields
Chapter 24 Magnetic Fields 1 Magnetic Poles Every magnet, regardless of its shape, has two poles Called north and south poles Poles exert forces on one another Similar to the way electric charges exert
More informationMagnets. Domain = small magnetized region of a magnetic material. all the atoms are grouped together and aligned
Magnetic Fields Magnets Domain = small magnetized region of a magnetic material all the atoms are grouped together and aligned Magnets Ferromagnetic materials domains can be forced to line up by applying
More informationName: Class: Date: AP Physics Spring 2012 Q6 Practice. Multiple Choice Identify the choice that best completes the statement or answers the question.
ame: Class: Date: ID: A AP Physics Spring 2012 Q6 Practice Multiple Choice Identify the choice that best completes the statement or answers the question. 1. (2 points) A potential difference of 115 V across
More informationChapter 31. Faraday s Law
Chapter 31 Faraday s Law 1 Ampere s law Magnetic field is produced by time variation of electric field B s II I d d μ o d μo με o o E ds E B Induction A loop of wire is connected to a sensitive ammeter
More informationPhysics 112. Study Notes for Exam II
Chapter 20 Electric Forces and Fields Physics 112 Study Notes for Exam II 4. Electric Field Fields of + and point charges 5. Both fields and forces obey (vector) superposition Example 20.5; Figure 20.29
More informationCh 30 - Sources of Magnetic Field
Ch 30 - Sources of Magnetic Field Currents produce Magnetism? 1820, Hans Christian Oersted: moving charges produce a magnetic field. The direction of the field is determined using a RHR. Oersted (1820)
More informationPhysics Will Farmer. May 5, Physics 1120 Contents 2
Physics 1120 Will Farmer May 5, 2013 Contents Physics 1120 Contents 2 1 Charges 3 1.1 Terms................................................... 3 1.2 Electric Charge..............................................
More informationPhysics 2020 Exam 2 Constants and Formulae
Physics 2020 Exam 2 Constants and Formulae Useful Constants k e = 8.99 10 9 N m 2 /C 2 c = 3.00 10 8 m/s ɛ = 8.85 10 12 C 2 /(N m 2 ) µ = 4π 10 7 T m/a e = 1.602 10 19 C h = 6.626 10 34 J s m p = 1.67
More informationYell if you have any questions
Class 36: Outline Hour 1: Concept Review / Overview PRS Questions Possible Exam Questions Hour : Sample Exam Yell if you have any questions P36-1 Before Starting All of your grades should now be posted
More informationChapter 22, Magnetism. Magnets
Chapter 22, Magnetism Magnets Poles of a magnet (north and south ) are the ends where objects are most strongly attracted. Like poles repel each other and unlike poles attract each other Magnetic poles
More informationGeneral Physics (PHY 2140)
General Physics (PHY 2140) Lecture 15 Electricity and Magnetism Magnetism Applications of magnetic forces Induced voltages and induction Magnetic flux and induced emf Faraday s law http://www.physics.wayne.edu/~apetrov/phy2140/
More informationr where the electric constant
1.0 ELECTROSTATICS At the end of this topic, students will be able to: 10 1.1 Coulomb s law a) Explain the concepts of electrons, protons, charged objects, charged up, gaining charge, losing charge, charging
More informationMagnetostatics III. P.Ravindran, PHY041: Electricity & Magnetism 1 January 2013: Magntostatics
Magnetostatics III Magnetization All magnetic phenomena are due to motion of the electric charges present in that material. A piece of magnetic material on an atomic scale have tiny currents due to electrons
More informationChapter 1 The Electric Force
Chapter 1 The Electric Force 1. Properties of the Electric Charges 1- There are two kinds of the electric charges in the nature, which are positive and negative charges. - The charges of opposite sign
More informationFinal on December Physics 106 R. Schad. 3e 4e 5c 6d 7c 8d 9b 10e 11d 12e 13d 14d 15b 16d 17b 18b 19c 20a
Final on December11. 2007 - Physics 106 R. Schad YOUR NAME STUDENT NUMBER 3e 4e 5c 6d 7c 8d 9b 10e 11d 12e 13d 14d 15b 16d 17b 18b 19c 20a 1. 2. 3. 4. This is to identify the exam version you have IMPORTANT
More informationCHAPTER 29: ELECTROMAGNETIC INDUCTION
CHAPTER 29: ELECTROMAGNETIC INDUCTION So far we have seen that electric charges are the source for both electric and magnetic fields. We have also seen that these fields can exert forces on other electric
More informationr where the electric constant
0. Coulomb s law a) Explain the concepts of electrons, protons, charged objects, charged up, gaining charge, losing charge, grounding and charge conservation. b) Describe the motion of point charges when
More informationMagnetic Fields. or I in the filed. ! F = q! E. ! F = q! v! B. q! v. Charge q as source. Current I as source. Gauss s Law. Ampere s Law.
Magnetic Fields Charge q as source Gauss s Law Electric field E F = q E Faraday s Law Ampere-Maxwell Law Current I as source Magnetic field B Ampere s Law F = q v B Force on q in the field Force on q v
More informationTorque on a Current Loop
Today Chapter 19 Magnetism Torque on a current loop, electrical motor Magnetic field around a current carrying wire. Ampere s law Solenoid Material magnetism Clicker 1 Which of the following is wrong?
More informationChapter 21. Magnetism
Chapter 21 Magnetism Magnets Poles of a magnet are the ends where objects are most strongly attracted Two poles, called north and south Like poles repel each other and unlike poles attract each other Similar
More informationQuestions A hair dryer is rated as 1200 W, 120 V. Its effective internal resistance is (A) 0.1 Ω (B) 10 Ω (C) 12Ω (D) 120 Ω (E) 1440 Ω
Questions 4-41 36. Three 1/ µf capacitors are connected in series as shown in the diagram above. The capacitance of the combination is (A).1 µf (B) 1 µf (C) /3 µf (D) ½ µf (E) 1/6 µf 37. A hair dryer is
More informationCHAPTER 20 Magnetism
CHAPTER 20 Magnetism Units Magnets and Magnetic Fields Electric Currents Produce Magnetic Fields Force on an Electric Current in a Magnetic Field; Definition of B Force on Electric Charge Moving in a Magnetic
More informationLecture Sound Waves Review. Physics Help Q&A: tutor.leiacademy.org. Force on a Charge Moving in a Magnetic Field
Lecture 1101 Sound Waves Review Physics Help Q&A: tutor.leiacademy.org Force on a Charge Moving in a Magnetic Field A charge moving in a magnetic field can have a magnetic force exerted by the B-field.
More informationMaxwell s equations and EM waves. From previous Lecture Time dependent fields and Faraday s Law
Maxwell s equations and EM waves This Lecture More on Motional EMF and Faraday s law Displacement currents Maxwell s equations EM Waves From previous Lecture Time dependent fields and Faraday s Law 1 Radar
More informationPHYS ND semester Dr. Nadyah Alanazi. Lecture 16
1 PHYS 104 2 ND semester 1439-1440 Dr. Nadyah Alanazi Lecture 16 2 Chapter 29 Magnetic Field 29.1 Magnetic Fields and Forces 29.2 Magnetic Force Acting on a Current-Carrying Conductor 29.4 Motion of a
More informationElectricity & Magnetism
Ch 31 Faraday s Law Electricity & Magnetism Up to this point, we ve seen electric fields produced by electric charges... E =... and magnetic fields produced by moving charges... k dq E da = q in r 2 B
More informationAP Physics C. Magnetism - Term 4
AP Physics C Magnetism - Term 4 Interest Packet Term Introduction: AP Physics has been specifically designed to build on physics knowledge previously acquired for a more in depth understanding of the world
More informationGravity Electromagnetism Weak Strong
19. Magnetism 19.1. Magnets 19.1.1. Considering the typical bar magnet we can investigate the notion of poles and how they apply to magnets. 19.1.1.1. Every magnet has two distinct poles. 19.1.1.1.1. N
More informationElectromagnetic Induction (Chapters 31-32)
Electromagnetic Induction (Chapters 31-3) The laws of emf induction: Faraday s and Lenz s laws Inductance Mutual inductance M Self inductance L. Inductors Magnetic field energy Simple inductive circuits
More informationComplement to Physics 259
Complement to Physics 259 P. Marzlin 1 1 Institute for Quantum Information Science, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada I. INTRODUCTORY REMARKS The purpose
More informationLecture 10 Induction and Inductance Ch. 30
Lecture 10 Induction and Inductance Ch. 30 Cartoon - Faraday Induction Opening Demo - Thrust bar magnet through coil and measure the current Topics Faraday s Law Lenz s Law Motional Emf Eddy Currents LR
More informationMansfield Independent School District AP Physics C: Electricity and Magnetism Year at a Glance
Mansfield Independent School District AP Physics C: Electricity and Magnetism Year at a Glance First Six-Weeks Second Six-Weeks Third Six-Weeks Lab safety Lab practices and ethical practices Math and Calculus
More informationSlide 1 / 24. Electromagnetic Induction 2011 by Bryan Pflueger
Slide 1 / 24 Electromagnetic Induction 2011 by Bryan Pflueger Slide 2 / 24 Induced Currents If we have a galvanometer attached to a coil of wire we can induce a current simply by changing the magnetic
More informationDescribe the forces and torques exerted on an electric dipole in a field.
Learning Outcomes - PHYS 2015 Electric charges and forces: Describe the electrical nature of matter; Explain how an object can be charged; Distinguish between electrical conductors and insulators and the
More informationHandout 8: Sources of magnetic field. Magnetic field of moving charge
1 Handout 8: Sources of magnetic field Magnetic field of moving charge Moving charge creates magnetic field around it. In Fig. 1, charge q is moving at constant velocity v. The magnetic field at point
More information8. (6) Consider the circuit here with resistors R A, R B and R C. Rank the
General Physics II Exam 2 - Chs. 18B 21 - Circuits, Magnetism, EM Induction - Oct. 3, 2013 Name Rec. Instr. Rec. Time For full credit, make your work clear. Show formulas used, essential steps, and results
More informationVersion The diagram below represents lines of magnetic flux within a region of space.
1. The diagram below represents lines of magnetic flux within a region of space. 5. The diagram below shows an electromagnet made from a nail, a coil of insulated wire, and a battery. The magnetic field
More informationPHYS152 Lecture 8. Eunil Won Korea University. Ch 30 Magnetic Fields Due to Currents. Fundamentals of Physics by Eunil Won, Korea University
PHYS152 Lecture 8 Ch 3 Magnetic Fields Due to Currents Eunil Won Korea University Calculating the Magnetic Field Due to a Current Recall that we had the formula for the electrostatic force: d E = 1 ɛ dq
More informationr r 1 r r 1 2 = q 1 p = qd and it points from the negative charge to the positive charge.
MP204, Important Equations page 1 Below is a list of important equations that we meet in our study of Electromagnetism in the MP204 module. For your exam, you are expected to understand all of these, and
More informationPHY 131 Review Session Fall 2015 PART 1:
PHY 131 Review Session Fall 2015 PART 1: 1. Consider the electric field from a point charge. As you move farther away from the point charge, the electric field decreases at a rate of 1/r 2 with r being
More informationChapter 30. Induction and Inductance
Chapter 30 Induction and Inductance 30.2: First Experiment: 1. A current appears only if there is relative motion between the loop and the magnet (one must move relative to the other); the current disappears
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 informationAP Physics C Mechanics Objectives
AP Physics C Mechanics Objectives I. KINEMATICS A. Motion in One Dimension 1. The relationships among position, velocity and acceleration a. Given a graph of position vs. time, identify or sketch a graph
More informationYell if you have any questions
Class 36: Outline Hour 1: Concept Review / Overview PRS Questions Possible Exam Questions Hour : Sample Exam Yell if you have any questions P36-1 efore Starting All of your grades should now be posted
More informationPHYSICS 1B. Today s lecture: Motional emf. and. Lenz s Law. Electricity & Magnetism
PHYSICS 1B Today s lecture: Motional emf and Lenz s Law Electricity & Magnetism PHYSICS 1B Faraday s Law Applications of Faraday s Law - GFCI A GFCI is a Ground Fault Circuit Interrupter. It is designed
More informationLast time. Ampere's Law Faraday s law
Last time Ampere's Law Faraday s law 1 Faraday s Law of Induction (More Quantitative) The magnitude of the induced EMF in conducting loop is equal to the rate at which the magnetic flux through the surface
More informationIntroduction to Electromagnetism
Introduction to Electromagnetism Electric Field Lines If a charge feels an electrostatic force (Coulombic Force), it is said to be in an electric field. We like to represent electric fields with lines.
More informationChapter 5: Electromagnetic Induction
Chapter 5: Electromagnetic Induction 5.1 Magnetic Flux 5.1.1 Define and use magnetic flux Magnetic flux is defined as the scalar product between the magnetic flux density, B with the vector of the area,
More informationPhysics GRE: Electromagnetism. G. J. Loges 1. University of Rochester Dept. of Physics & Astronomy. xkcd.com/567/
Physics GRE: Electromagnetism G. J. Loges University of Rochester Dept. of Physics & stronomy xkcd.com/567/ c Gregory Loges, 206 Contents Electrostatics 2 Magnetostatics 2 3 Method of Images 3 4 Lorentz
More informationPhysics 1302W.400 Lecture 33 Introductory Physics for Scientists and Engineering II
Physics 1302W.400 Lecture 33 Introductory Physics for Scientists and Engineering II In today s lecture, we will discuss generators and motors. Slide 30-1 Announcement Quiz 4 will be next week. The Final
More informationAP Physics C. Electricity - Term 3
AP Physics C Electricity - Term 3 Interest Packet Term Introduction: AP Physics has been specifically designed to build on physics knowledge previously acquired for a more in depth understanding of the
More informationElectromagnetics in Medical Physics
Electromagnetics in Medical Physics Part 4. Biomagnetism Tong In Oh Department of Biomedical Engineering Impedance Imaging Research Center (IIRC) Kyung Hee University Korea tioh@khu.ac.kr Dot Product (Scalar
More informationLECTURE 17. Reminder Magnetic Flux
LECTURE 17 Motional EMF Eddy Currents Self Inductance Reminder Magnetic Flux Faraday s Law ε = dφ B Flux through one loop Φ B = BAcosθ da Flux through N loops Φ B = NBAcosθ 1 Reminder How to Change Magnetic
More informationGeneral Physics (PHY 2140)
General Physics (PHY 2140) Lecture 8 Electricity and Magnetism 1. Magnetism Application of magnetic forces Ampere s law 2. Induced voltages and induction Magnetic flux http://www.physics.wayne.edu/~alan/2140website/main.htm
More informationFaraday s Law. Faraday s Law of Induction Motional emf. Lenz s Law. Motors and Generators. Eddy Currents
Faraday s Law Faraday s Law of Induction Motional emf Motors and Generators Lenz s Law Eddy Currents Induced EMF A current flows through the loop when a magnet is moved near it, without any batteries!
More informationMASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Physics Spring 2014 Final Exam Equation Sheet. B( r) = µ o 4π
MASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Physics 8.02 Spring 2014 Final Exam Equation Sheet Force Law: F q = q( E ext + v q B ext ) Poynting Vector: S = ( E B) / µ 0 Force on Current Carrying
More information21 MAGNETIC FORCES AND MAGNETIC FIELDS
CHAPTER 1 MAGNETIC FORCES AND MAGNETIC FIELDS ANSWERS TO FOCUS ON CONCEPTS QUESTIONS 1 (d) Right-Hand Rule No 1 gives the direction of the magnetic force as x for both drawings A and B In drawing C, the
More informationMagnetic Induction Faraday, Lenz, Mutual & Self Inductance Maxwell s Eqns, E-M waves. Reading Journals for Tuesday from table(s)
PHYS 2015 -- Week 12 Magnetic Induction Faraday, Lenz, Mutual & Self Inductance Maxwell s Eqns, E-M waves Reading Journals for Tuesday from table(s) WebAssign due Friday night For exclusive use in PHYS
More informationChapter 5. Electromagnetic Induction
Chapter 5 Electromagnetic Induction Overview In the last chapter, we studied how a current produces a magnetic field. Here we will study the reverse effect: A magnetic field can produce an electric field
More informationwe can said that matter can be regarded as composed of three kinds of elementary particles; proton, neutron (no charge), and electron.
Physics II we can said that matter can be regarded as composed of three kinds of elementary particles; proton, neutron (no charge), and electron. Particle Symbol Charge (e) Mass (kg) Proton P +1 1.67
More informationPhysics 11b Lecture #13
Physics 11b Lecture #13 Faraday s Law S&J Chapter 31 Midterm #2 Midterm #2 will be on April 7th by popular vote Covers lectures #8 through #14 inclusive Textbook chapters from 27 up to 32.4 There will
More informationMagnetic Forces and Fields (Chapters 29-30)
Magnetic Forces and Fields (Chapters 29-30) Magnetism Magnetic Materials and Sources Magnetic Field, Magnetic Force Force on Moving Electric Charges Lorentz Force Force on Current Carrying Wires Applications
More information/20 /20 /20 /60. Dr. Galeazzi PHY207 Test #3 November 20, I.D. number:
Signature: Name: I.D. number: You must do ALL the problems Each problem is worth 0 points for a total of 60 points. TO GET CREDIT IN PROBLEMS AND 3 YOU MUST SHOW GOOD WORK. CHECK DISCUSSION SECTION ATTENDED:
More informationCh. 23 Electromagnetic Induction, AC Circuits, And Electrical Technologies
Ch. 23 Electromagnetic Induction, AC Circuits, And Electrical Technologies Induced emf - Faraday s Experiment When a magnet moves toward a loop of wire, the ammeter shows the presence of a current When
More informationMagnetic Fields and Forces
Nicholas J. Giordano www.cengage.com/physics/giordano Chapter 20 Magnetic Fields and Forces Marilyn Akins, PhD Broome Community College Magnetism Magnetic fields are produced by moving electric charges
More informationFundamental Constants
Fundamental Constants Atomic Mass Unit u 1.660 540 2 10 10 27 kg 931.434 32 28 MeV c 2 Avogadro s number N A 6.022 136 7 36 10 23 (g mol) 1 Bohr magneton μ B 9.274 015 4(31) 10-24 J/T Bohr radius a 0 0.529
More informationCircuits Capacitance of a parallel-plate capacitor : C = κ ε o A / d. (ρ = resistivity, L = length, A = cross-sectional area) Resistance : R = ρ L / A
k = 9.0 x 109 N m2 / C2 e = 1.60 x 10-19 C ε o = 8.85 x 10-12 C2 / N m2 Coulomb s law: F = k q Q / r2 (unlike charges attract, like charges repel) Electric field from a point charge : E = k q / r2 ( towards
More informationChapter 20: Electromagnetic Induction. PHY2054: Chapter 20 1
Chapter 20: Electromagnetic Induction PHY2054: Chapter 20 1 Electromagnetic Induction Magnetic flux Induced emf Faraday s Law Lenz s Law Motional emf Magnetic energy Inductance RL circuits Generators and
More informationProblem Fig
Problem 9.53 A flexible circular loop 6.50 cm in diameter lies in a magnetic field with magnitude 0.950 T, directed into the plane of the page, as shown. The loop is pulled at the points indicated by the
More informationMagnetic Forces and Fields (Chapters 32)
Magnetic Forces and Fields (Chapters 32) Magnetism Magnetic Materials and Sources Magnetic Field, B Magnetic Force Force on Moving Electric Charges Lorentz Force Force on Current Carrying Wires Applications
More informationGeneral Physics II. Electromagnetic Induction and Electromagnetic Waves
General Physics II Electromagnetic Induction and Electromagnetic Waves 1 Induced emf We have seen that an electric current produces a magnetic field. Michael Faraday demonstrated that a magnetic field
More informationSelf-inductance A time-varying current in a circuit produces an induced emf opposing the emf that initially set up the time-varying current.
Inductance Self-inductance A time-varying current in a circuit produces an induced emf opposing the emf that initially set up the time-varying current. Basis of the electrical circuit element called an
More informationChapters 34,36: Electromagnetic Induction. PHY2061: Chapter
Chapters 34,36: Electromagnetic Induction PHY2061: Chapter 34-35 1 Electromagnetic Induction Magnetic flux Induced emf Faraday s Law Lenz s Law Motional emf Magnetic energy Inductance RL circuits Generators
More informationChapter 2 Basics of Electricity and Magnetism
Chapter 2 Basics of Electricity and Magnetism My direct path to the special theory of relativity was mainly determined by the conviction that the electromotive force induced in a conductor moving in a
More informationDHANALAKSHMI SRINIVASAN INSTITUTE OF RESEARCH AND TECHNOLOGY
DHANALAKSHMI SRINIVASAN INSTITUTE OF RESEARCH AND TECHNOLOGY SIRUVACHUR-621113 ELECTRICAL AND ELECTRONICS DEPARTMENT 2 MARK QUESTIONS AND ANSWERS SUBJECT CODE: EE 6302 SUBJECT NAME: ELECTROMAGNETIC THEORY
More informationHomework. Reading: Chap. 29, Chap. 31 and Chap. 32. Suggested exercises: 29.17, 29.19, 29.22, 29.23, 29.24, 29.26, 29.27, 29.29, 29.30, 29.31, 29.
Homework Reading: Chap. 29, Chap. 31 and Chap. 32 Suggested exercises: 29.17, 29.19, 29.22, 29.23, 29.24, 29.26, 29.27, 29.29, 29.30, 29.31, 29.32 Problems: 29.49, 29.51, 29.52, 29.57, 29.58, 29.59, 29.63,
More informationGen. Phys. II Exam 2 - Chs. 21,22,23 - Circuits, Magnetism, EM Induction Mar. 5, 2018
Gen. Phys. II Exam 2 - Chs. 21,22,23 - Circuits, Magnetism, EM Induction Mar. 5, 2018 Rec. Time Name For full credit, make your work clear. Show formulas used, essential steps, and results with correct
More informationiclicker: which statements are correct?
iclicker: which statements are correct? 1. Electric field lines must originate and terminate on charges 2. Magnetic field lines are always closed A: 1&2 B: only 1 C: only 2 D: neither 2 Inductive E-field:
More informationIII.Sources of Magnetic Fields - Ampere s Law - solenoids
Magnetism I. Magnetic Field - units, poles - effect on charge II. Magnetic Force on Current - parallel currents, motors III.Sources of Magnetic Fields - Ampere s Law - solenoids IV.Magnetic Induction -
More informationChapter 30. Induction and Inductance
Chapter 30 Induction and Inductance 30.2: First Experiment: 1. A current appears only if there is relative motion between the loop and the magnet (one must move relative to the other); the current disappears
More informationChapter 23 Magnetic Flux and Faraday s Law of Induction
Chapter 23 Magnetic Flux and Faraday s Law of Induction 1 Overview of Chapter 23 Induced Electromotive Force Magnetic Flux Faraday s Law of Induction Lenz s Law Mechanical Work and Electrical Energy Generators
More informationb) (4) How large is the current through the 2.00 Ω resistor, and in which direction?
General Physics II Exam 2 - Chs. 19 21 - Circuits, Magnetism, EM Induction - Sep. 29, 2016 Name Rec. Instr. Rec. Time For full credit, make your work clear. Show formulas used, essential steps, and results
More informationChapter 32. Inductance
Chapter 32 Inductance Joseph Henry 1797 1878 American physicist First director of the Smithsonian Improved design of electromagnet Constructed one of the first motors Discovered self-inductance Unit of
More informationCh. 28: Sources of Magnetic Fields
Ch. 28: Sources of Magnetic Fields Electric Currents Create Magnetic Fields A long, straight wire A current loop A solenoid Slide 24-14 Biot-Savart Law Current produces a magnetic field The Biot-Savart
More informationMichael Faraday. Chapter 31. EMF Produced by a Changing Magnetic Field, 1. Induction. Faraday s Law
Michael Faraday Chapter 31 Faraday s Law Great experimental physicist and chemist 1791 1867 Contributions to early electricity include: Invention of motor, generator, and transformer Electromagnetic induction
More informationElectrical polarization. Figure 19-5 [1]
Electrical polarization Figure 19-5 [1] Properties of Charge Two types: positive and negative Like charges repel, opposite charges attract Charge is conserved Fundamental particles with charge: electron
More informationChapter 30 Sources of the magnetic field
Chapter 30 Sources of the magnetic field Force Equation Point Object Force Point Object Field Differential Field Is db radial? Does db have 1/r2 dependence? Biot-Savart Law Set-Up The magnetic field is
More informationChapter 27, 28 & 29: Magnetism & Electromagnetic Induction
Chapter 27, 28 & 29: Magnetism & Electromagnetic Induction The Magnetic Field The Magnetic Force on Moving Charges The Motion of Charged Particles in a Magnetic Field The Magnetic Force Exerted on a Current-Carrying
More information