Electromagnetic Induction

Size: px
Start display at page:

Download "Electromagnetic Induction"

Transcription

1 Electromagnetic Induction Name Section Theory Electromagnetic induction employs the concept magnetic flux. Consider a conducting loop of area A in a magnetic field with magnitude B. The flux Φ is proportional to the number of field lines passing through the loop. Φ = BA cos θ (1) The cosine term in Equation 1 arises from the fact that the number of field lines passing through the loop will change depending on the orientation of the loop relative to the field. The direction of A is taken to be normal to the plane of the loop, as shown in Figure 1. Figure 1: Magnetic Flux The angle θ is the angle between A and B; intuitively, this makes sense. If B and A are parallel (θ = 0 ) then cos θ = 1 and the flux is maximum through A. If B and A are perpendicular (θ = 90 ) then cos θ = 0 and the flux is 0. In general, what Equation 1 gives is the product of A and the component of B parallel to A (perpendicular to the plane of the loop). It was Faraday who first concluded that the emf E induced in a conducting loop is dependent upon the time rate of change of the magnetic flux through the loop. E = Φ t (2) This is known as Faraday s law of induction. The minus sign is an indication of the polarity of the induced emf. If we consider the current produced by this emf and its effect, then 1

2 An induced emf generates a current whose magnetic field opposes the change in flux that produced it. This is known as Lenz s law, and arises from the conservation of energy. Suppose that the induced current produced a magnetic field that added to the original field. This would increase the flux through the loop, which would give rise to a greater current, which would then produce an even greater flux, produce an even greater current, and so on. In physics, you can t get something for nothing! Apparatus Power supply, Galvanometer, Wires, Solenoid, Bar magnet, Decade resistance box, Switch, Magnetic compass. Procedure In this experiment you will use a solenoid as the conducting loop; remember that a solenoid is a series of conducting loops arranged cylindrically. The flux, hence the induced emf, is proportional to the number of loops (turns) N so that Faraday s law becomes E = N Φ t (3) The Galvanometer A galvanometer is essentially an ammeter which shows the magnitude and direction of the current flowing through it. It uses some of the same principles we are studying here, and is the basis for all analog ammeters and voltmeters. However, these require the addition of an appropriate series or parallel resistance, since the maximum current that the galvanometer can handle in either direction is only 500µA (500x10 6 A). Care must be exercised at all times to ensure that you do not send more current than this through it. 5V DC I Decade Galvanometer Since the rules for electricity and magnetism are based on positive test charges and the flow of conventional current (positive charge), we need to know how the galvanometer responds. Put the decade box, galvanometer, and switch in a series circuit with the power supply (COM, +5V) as shown above. [Note: If your galvanometer has (+) and (-) connections, disregard these 1 - they only confuse the issue.] Use Ohm s Law to calculate the resistance needed in the circuit for this full-scale this current, placing the value in Table 1. Set a resistance 20% higher than this on the decade box and have your circuit checked by the lab instructor before proceeding. 1 They are unnecessary in my opinion, as the galvanometer needle deflects in both directions. 2

3 Potential of power supply (V) 5.0 Full-scale galvanometer current (A) 500x10 6 Resistance for circuit (Ω) 20% higher resistance (Ω) Table 1: Circuit Resistance Conventional current is the flow of positive charge around a circuit from the (+) side of the potential to the (-) side. Follow the connections from the (+) side of the power supply around the circuit and through the galvanometer. Throw the switch and note which direction (left or right) the needle on the galvanometer deflects. Is the deflection of the galvanometer needle in the same direction as the flow of conventional current through the galvanometer or in the opposite direction of the flow of conventional current through it? The Electromagnet Disassemble the previous circuit. We need a consistent orientation for the remainder of the experiment, so proceed as follows: Place the solenoid on the table in front of you such that you are perpendicular to its axis; i.e., you will be looking at the coils of the solenoid rather than through it. Turn, if necessary, such that the connections on the solenoid are at the top rear of the solenoid from your vantage point. Place the power supply behind the solenoid and connect it (COM, +5V) to the solenoid. Hold the compass at the left end of the solenoid, turn on the power supply, and note what happens to the compass needle. Turn off the power supply and repeat with the compass at the right end of the solenoid. Turn off the power supply, switch the leads, and repeat. When conventional current flows through the solenoid from the left side to the right side, which end of the solenoid is the N magnetic pole? S magnetic pole? What about when conventional current flows through the solenoid from the right side to the left side - which end of the solenoid is N? S? This should help you verify your diagrams in the next procedure. 3

4 Induction (Coil and Magnet) Replace the power supply with the galvanometer this arrangement shown in Figure 2. Figure 2: The Solenoid On a separate sheet of paper, provide a series of sketches similar to Figure 2 with the results of the following investigations: 1. N end of the magnet inserted into right end of solenoid 2. N end of magnet removed from the right end of the solenoid 3. S end of the magnet inserted into right end of solenoid 4. S end of magnet removed from the right end of the solenoid 5. N end of the magnet inserted into left end of solenoid 6. N end of magnet removed from the left end of the solenoid 7. S end of the magnet inserted into left end of solenoid 8. S end of magnet removed from the left end of the solenoid On each, indicate the direction of the needle deflection as shown on the galvanometer, the direction of the induced conventional current through the solenoid, and the direction of the induced magnetic field in the solenoid. In order to do this, you will need to know how the coils are wound around the solenoid. If viewed from either end; i.e., when looking through it, the coils are clockwise from your end to the far end. The observations in your diagrams should agree with predictions made with the right-hand rule. In the above situations, the magnet was moved into and out of a stationary solenoid. What would happen if the solenoid was moved toward and away from a stationary magnet? Hold the magnet stationary on the right side of the solenoid (N end of the magnet closest to the solenoid) and move the solenoid to the right until the N end of the magnet is inside the solenoid. After this, move the solenoid to the left until the magnet is again outside the solenoid. Were your results analogous to situations 1 and 2 above? Would you expect similar results in 3-8? Why or why not? 4

5 What is induced in the solenoid if there is no relative motion between the magnet and solenoid; i.e., the magnet is held stationary inside or outside the solenoid? See if you can induce a current in the solenoid in any other way not already investigated. observations here. Record your 5

6 Pre-Lab: Electromagnetic Induction Name Section Answer the questions at the bottom of this sheet, below the line - continue on the back if you need more room. Any calculations should be shown in full. 1. What is Faraday s law of induction? 2. What is Lenz s law? 3. What is conventional current? 6

Magnetic flux. where θ is the angle between the magnetic field and the area vector. The unit of magnetic flux is the weber. 1 Wb = 1 T m 2.

Magnetic flux. where θ is the angle between the magnetic field and the area vector. The unit of magnetic flux is the weber. 1 Wb = 1 T m 2. Magnetic flux Magnetic flux is a measure of the number of magnetic field lines passing through something, such as a loop. If we define the area of the loop as a vector, with its direction perpendicular

More information

Chapter 27, 28 & 29: Magnetism & Electromagnetic Induction. Magnetic flux Faraday s and Lenz s law Electromagnetic Induction Ampere s law

Chapter 27, 28 & 29: Magnetism & Electromagnetic Induction. Magnetic flux Faraday s and Lenz s law Electromagnetic Induction Ampere s law Chapter 27, 28 & 29: Magnetism & Electromagnetic Induction Magnetic flux Faraday s and Lenz s law Electromagnetic Induction Ampere s law 1 Magnetic Flux and Faraday s Law of Electromagnetic Induction We

More information

PHYSICS Fall Lecture 15. Electromagnetic Induction and Faraday s Law

PHYSICS Fall Lecture 15. Electromagnetic Induction and Faraday s Law PHYSICS 1444-001 Fall 2012 Lecture 15 Electromagnetic Induction and Faraday s Law A current can be produced by a changing magnetic field First shown in an experiment by Michael Faraday Induced emf A primary

More information

Chapter 23 Magnetic Flux and Faraday s Law of Induction

Chapter 23 Magnetic Flux and Faraday s Law of Induction Chapter 23 Magnetic Flux and Faraday s Law of Induction Recall: right hand rule 2 10/28/2013 Units of Chapter 23 Induced Electromotive Force Magnetic Flux Faraday s Law of Induction Lenz s Law Mechanical

More information

Chapter 21 Magnetic Induction Lecture 12

Chapter 21 Magnetic Induction Lecture 12 Chapter 21 Magnetic Induction Lecture 12 21.1 Why is it called Electromagnetism? 21.2 Magnetic Flux and Faraday s Law 21.3 Lenz s Law and Work-Energy Principles 21.4 Inductance 21.5 RL Circuits 21.6 Energy

More information

Electromagnetic Induction. Bo Zhou Faculty of Science, Hokudai

Electromagnetic Induction. Bo Zhou Faculty of Science, Hokudai Electromagnetic Induction Bo Zhou Faculty of Science, Hokudai Oersted's law Oersted s discovery in 1820 that there was a close connection between electricity and magnetism was very exciting until then,

More information

FARADAY S AND LENZ LAW B O O K P G

FARADAY S AND LENZ LAW B O O K P G FARADAY S AND LENZ LAW B O O K P G. 4 3 6-438 MOTIONAL EMF AND MAGNETIC FLUX (DERIVIATION) Motional emf = vbl Let a conducting rod being moved through a magnetic field B During time t 0 the rod has been

More information

Electricity & Optics

Electricity & Optics Physics 24100 Electricity & Optics Lecture 16 Chapter 28 sec. 1-3 Fall 2017 Semester Professor Koltick Magnetic Flux We define magnetic flux in the same way we defined electric flux: φ e = n E da φ m =

More information

LECTURE 23 INDUCED EMF. Instructor: Kazumi Tolich

LECTURE 23 INDUCED EMF. Instructor: Kazumi Tolich LECTURE 23 INDUCED EMF Instructor: Kazumi Tolich Lecture 23 2 Reading chapter 23.1 to 23.4. Induced emf Magnetic flux Faraday s law Lenz s law Quiz: 1 3 Consider the circuits shown. Which of the following

More information

General Physics (PHY 2140)

General 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 information

MAGNETIC CIRCUITS. Magnetic Circuits

MAGNETIC CIRCUITS. Magnetic Circuits Basic Electrical Theory What is a magnetic circuit? To better understand magnetic circuits, a basic understanding of the physical qualities of magnetic circuits will be necessary. EO 1.8 EO 1.9 EO 1.10

More information

Can a Magnetic Field Produce a Current?

Can a Magnetic Field Produce a Current? Can a Magnetic Field Produce a Current? In our study of magnetism we learned that an electric current through a wire, or moving electrically charged objects, produces a magnetic field. Could the reverse

More information

Chapter 10 Notes: Magnetic Induction

Chapter 10 Notes: Magnetic Induction Chapter 10 Notes: Magnetic Induction How can a changing magnetic field cause an electric current to flow? Eleven years after the connection between magnetism and electricity was first reported by Oersted,

More information

Application Of Faraday s Law

Application Of Faraday s Law Application Of Faraday s Law Dr Miguel Cavero September 2, 2014 Application Of Faraday s Law September 2, 2014 1 / 23 The PHYS120 Exam will be divided into three sections as follows: Section A: Short Questions

More information

Chapter 5: Electromagnetic Induction

Chapter 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 information

Faraday's Law ds B B G G ΦB B ds Φ ε = d B dt

Faraday's Law ds B B G G ΦB B ds Φ ε = d B dt Faraday's Law ds ds ε= d Φ dt Φ Global Review Electrostatics» motion of q in external E-field» E-field generated by Σq i Magnetostatics» motion of q and i in external -field» -field generated by I Electrodynamics»

More information

Chapter 22. Induction

Chapter 22. Induction Chapter 22 Induction Induced emf A current can be produced by a changing magnetic field First shown in an experiment by Michael Faraday A primary coil is connected to a battery A secondary coil is connected

More information

Electromagnetic Induction Practice Problems Homework PSI AP Physics B

Electromagnetic Induction Practice Problems Homework PSI AP Physics B Electromagnetic Induction Practice Problems Homework PSI AP Physics B Name Multiple Choice Questions 1. A square loop of wire is placed in a uniform magnetic field perpendicular to the magnetic lines.

More information

PHYSICS. Chapter 30 Lecture FOR SCIENTISTS AND ENGINEERS A STRATEGIC APPROACH 4/E RANDALL D. KNIGHT

PHYSICS. Chapter 30 Lecture FOR SCIENTISTS AND ENGINEERS A STRATEGIC APPROACH 4/E RANDALL D. KNIGHT PHYSICS FOR SCIENTISTS AND ENGINEERS A STRATEGIC APPROACH 4/E Chapter 30 Lecture RANDALL D. KNIGHT Chapter 30 Electromagnetic Induction IN THIS CHAPTER, you will learn what electromagnetic induction is

More information

PHYS 1442 Section 004 Lecture #14

PHYS 1442 Section 004 Lecture #14 PHYS 144 Section 004 Lecture #14 Wednesday March 5, 014 Dr. Chapter 1 Induced emf Faraday s Law Lenz Law Generator 3/5/014 1 Announcements After class pickup test if you didn t Spring break Mar 10-14 HW7

More information

Electromagnetic Induction

Electromagnetic Induction Lab 9. Electromagnetic Induction Goals To understand what it means to have magnetic flux through a loop or coil in a circuit. To understand and apply Lenz s law and the right hand rule for magnetic fields

More information

PHY 1214 General Physics II

PHY 1214 General Physics II PHY 1214 General Physics II Lecture 20 Magnetic Flux and Faraday s Law July 6-7, 2005 Weldon J. Wilson Professor of Physics & Engineering Howell Hall 221H wwilson@ucok.edu Lecture Schedule (Weeks 4-6)

More information

Chapter 9 FARADAY'S LAW Recommended Problems:

Chapter 9 FARADAY'S LAW Recommended Problems: Chapter 9 FARADAY'S LAW Recommended Problems: 5,7,9,10,11,13,15,17,20,21,28,29,31,32,33,34,49,50,52,58,63,64. Faraday's Law of Induction We learned that e. current produces magnetic field. Now we want

More information

Material World: Electricity

Material World: Electricity 17. Coulomb s Law The force, F, between two objects with charge q1 and q2, is given by: k q q 1 2 F -, where r = distance between the two charges in meters 2 r k = Coulomb's constant = 9 X 10 9 m 2 /C

More information

Induction_P1. 1. [1 mark]

Induction_P1. 1. [1 mark] Induction_P1 1. [1 mark] Two identical circular coils are placed one below the other so that their planes are both horizontal. The top coil is connected to a cell and a switch. The switch is closed and

More information

PHY222 Lab 10 - Magnetic Fields: Magnetic Flux and. Lenz's Law Currents induced in coils by magnets and by other coils

PHY222 Lab 10 - Magnetic Fields: Magnetic Flux and. Lenz's Law Currents induced in coils by magnets and by other coils PHY222 Lab 10 - Magnetic Fields: Magnetic Flux and Print Your Name Lenz's Law Currents induced in coils by magnets and by other coils Print Your Partners' Names You will return this handout to the instructor

More information

Our goal for today. 1. To go over the pictorial approach to Lenz s law.

Our goal for today. 1. To go over the pictorial approach to Lenz s law. Our goal for today 1. To go over the pictorial approach to Lenz s law. Lenz s Law Exposing a coil or loop to a changing magnetic flux will generate a current if the circuit is complete. The direction of

More information

Ch. 23 Electromagnetic Induction, AC Circuits, And Electrical Technologies

Ch. 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 information

FXA 2008 Φ = BA. Candidates should be able to : Define magnetic flux. Define the weber (Wb). Select and use the equation for magnetic flux :

FXA 2008 Φ = BA. Candidates should be able to : Define magnetic flux. Define the weber (Wb). Select and use the equation for magnetic flux : 1 Candidates should be able to : Define magnetic flux. Define the weber (Wb). Select and use the equation for magnetic flux : Φ = BAcosθ MAGNETIC FLUX (Φ) As we have already stated, a magnetic field is

More information

Electromagnetic Induction

Electromagnetic Induction Electromagnetic Induction PHY232 Remco Zegers zegers@nscl.msu.edu Room W109 cyclotron building http://www.nscl.msu.edu/~zegers/phy232.html previously: electric currents generate magnetic field. If a current

More information

Lab 7: Magnetism Introduction Magnets need no introduction (i.e. introduction to be added in future revision).

Lab 7: Magnetism Introduction Magnets need no introduction (i.e. introduction to be added in future revision). CSUEB Physics 1780 Lab 7: Magnetism Page 1 Lab 7: Magnetism Introduction Magnets need no introduction (i.e. introduction to be added in future revision). Experiments The purpose of these experiments is

More information

Faraday s Law. Lecture 17. Chapter 33. Physics II. Course website:

Faraday s Law. Lecture 17. Chapter 33. Physics II. Course website: Lecture 17 Chapter 33 Physics II Faraday s Law Course website: http://faculty.uml.edu/andriy_danylov/teaching/physicsii Electromagnetic induction We saw that a magnetic field could be produced with an

More information

PHYS 1444 Section 003 Lecture #18

PHYS 1444 Section 003 Lecture #18 PHYS 1444 Section 003 Lecture #18 Wednesday, Nov. 2, 2005 Magnetic Materials Ferromagnetism Magnetic Fields in Magnetic Materials; Hysteresis Induced EMF Faraday s Law of Induction Lenz s Law EMF Induced

More information

Can a Magnetic Field Produce a Current?

Can a Magnetic Field Produce a Current? Can a Magnetic Field Produce a Current? In our study of magnetism we learned that an electric current through a wire, or moving electrically charged objects, produces a magnetic field. Could the reverse

More information

General Physics II. Electromagnetic Induction and Electromagnetic Waves

General 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 information

DO PHYSICS ONLINE MOTORS AND GENERATORS FARADAY S LAW ELECTROMAGNETIC INDUCTION

DO PHYSICS ONLINE MOTORS AND GENERATORS FARADAY S LAW ELECTROMAGNETIC INDUCTION DO PHYSICS ONLINE MOTORS AND GENERATORS FARADAY S LAW ELECTROMAGNETIC INDUCTION English Michael Faraday (1791 1867) who experimented with electric and magnetic phenomena discovered that a changing magnetic

More information

Electromagnetic Induction and Faraday s Law

Electromagnetic Induction and Faraday s Law Electromagnetic Induction and Faraday s Law Induced EMF Almost 200 years ago, Faraday looked for evidence that a magnetic field would induce an electric current with this apparatus: He found no evidence

More information

Slide 1 / 24. Electromagnetic Induction 2011 by Bryan Pflueger

Slide 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 information

Lenz s Law (Section 22.5)

Lenz s Law (Section 22.5) Lenz s Law (Section 22.5) : Thursday, 25 of February 7:00 9:00 pm Rooms: Last Name Room (Armes) Seats A - F 201 122 G - R 200 221 S - Z 205 128 2016-02-21 Phys 1030 General Physics II (Gericke) 1 1) Charging

More information

Chapter 23: Magnetic Flux and Faraday s Law of Induction

Chapter 23: Magnetic Flux and Faraday s Law of Induction Chapter 3: Magnetic Flux and Faraday s Law of Induction Answers Conceptual Questions 6. Nothing. In this case, the break prevents a current from circulating around the ring. This, in turn, prevents the

More information

Induction and Inductance

Induction and Inductance Welcome Back to Physics 1308 Induction and Inductance Michael Faraday 22 September 1791 25 August 1867 Announcements Assignments for Tuesday, November 6th: - Reading: Chapter 30.6-30.8 - Watch Videos:

More information

Physics 201. Professor P. Q. Hung. 311B, Physics Building. Physics 201 p. 1/1

Physics 201. Professor P. Q. Hung. 311B, Physics Building. Physics 201 p. 1/1 Physics 201 p. 1/1 Physics 201 Professor P. Q. Hung 311B, Physics Building Physics 201 p. 2/1 Magnetic flux What is a magnetic flux? This is very similar to the concept of an electric flux through an area

More information

Induction and Inductance

Induction and Inductance Induction and Inductance Key Contents Faraday s law: induced emf Induction and energy transfer Inductors and inductance RL circuits Magnetic energy density The First Experiment 1. A current appears only

More information

Faraday s Law. Lecture 17. Chapter 33. Physics II. Course website:

Faraday s Law. Lecture 17. Chapter 33. Physics II. Course website: Lecture 17 Chapter 33 Physics II Faraday s Law Course website: http://faculty.uml.edu/andriy_danylov/teaching/physicsii Lecture Capture: http://echo360.uml.edu/danylov201415/physics2spring.html Electromagnetic

More information

PHYSICS - GIANCOLI CALC 4E CH 29: ELECTROMAGNETIC INDUCTION.

PHYSICS - GIANCOLI CALC 4E CH 29: ELECTROMAGNETIC INDUCTION. !! www.clutchprep.com CONCEPT: ELECTROMAGNETIC INDUCTION A coil of wire with a VOLTAGE across each end will have a current in it - Wire doesn t HAVE to have voltage source, voltage can be INDUCED i V Common

More information

Michael Faraday. Chapter 31. EMF Produced by a Changing Magnetic Field, 1. Induction. Faraday s Law

Michael 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 information

Magnetism. and its applications

Magnetism. and its applications Magnetism and its applications Laws of Magnetism 1) Like magnetic poles repel, and 2) unlike poles attract. Magnetic Direction and Strength Law 3 - Magnetic force, either attractive or repelling varies

More information

Slide 1 / 50. Electromagnetic Induction and Faraday s Law

Slide 1 / 50. Electromagnetic Induction and Faraday s Law Slide 1 / 50 Electromagnetic Induction and Faraday s Law Slide 2 / 50 Electromagnetic Induction and Faraday s Law Induced EMF Faraday s Law of Induction Lenz s Law EMF Induced in a Moving Conductor Changing

More information

Slide 1 / 50. Slide 2 / 50. Slide 3 / 50. Electromagnetic Induction and Faraday s Law. Electromagnetic Induction and Faraday s Law.

Slide 1 / 50. Slide 2 / 50. Slide 3 / 50. Electromagnetic Induction and Faraday s Law. Electromagnetic Induction and Faraday s Law. Electromagnetic Induction and Faraday s Law Slide 1 / 50 Electromagnetic Induction and Faraday s Law Slide 2 / 50 Induced EMF Faraday s Law of Induction Lenz s Law EMF Induced in a Moving Conductor Changing

More information

Faraday 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. 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 information

Fig. 2.1 I =... A [2] Suggest why it would be impossible for overhead cables carrying an alternating current to float in the Earth s magnetic field.

Fig. 2.1 I =... A [2] Suggest why it would be impossible for overhead cables carrying an alternating current to float in the Earth s magnetic field. 1 (a) Fig. 2.1 shows a horizontal current-carrying wire placed in a uniform magnetic field. I region of uniform magnetic field wire Fig. 2.1 The magnetic field of flux density 0.070 T is at right angles

More information

Electromagnetism Notes 1 Magnetic Fields

Electromagnetism Notes 1 Magnetic Fields Electromagnetism Notes 1 Magnetic Fields Magnets can or other magnets. They are able to exert forces on each other without touching because they are surrounded by. Magnetic Flux refers to Areas with many

More information

Introduction: Recall what the Biot-Savart Law and, more generally, Ampere s Law say: Electric Currents Create Magnetic Fields

Introduction: Recall what the Biot-Savart Law and, more generally, Ampere s Law say: Electric Currents Create Magnetic Fields Electromagnetic Induction I really don t like the order in which your author presents the material in this chapter, so I m going put in a slightly different order. Introduction: Recall what the Biot-Savart

More information

C. Incorrect! Use the formula for magnetic flux. This is the product of magnetic field, times area, times the angle between them.

C. Incorrect! Use the formula for magnetic flux. This is the product of magnetic field, times area, times the angle between them. AP Physics - Problem Drill 17: Electromagnetism Instruction: (1) Read the problem statement and answer choices carefully (2) Work the problems on paper as 1. A house has a wall that has an area of 28 m

More information

Demo: Solenoid and Magnet. Topics. Chapter 22 Electromagnetic Induction. EMF Induced in a Moving Conductor

Demo: Solenoid and Magnet. Topics. Chapter 22 Electromagnetic Induction. EMF Induced in a Moving Conductor Topics Chapter 22 Electromagnetic Induction EMF Induced in a Moving Conductor Magnetic Flux EMF Induced in a Moving Conductor Demo: Solenoid and Magnet v 1 EMF Induced in a Moving Conductor q Work done

More information

Electromagnetic Induction & Inductors

Electromagnetic Induction & Inductors Electromagnetic Induction & Inductors 1 Revision of Electromagnetic Induction and Inductors (Much of this material has come from Electrical & Electronic Principles & Technology by John Bird) Magnetic Field

More information

> What happens when the poles of two magnets are brought close together? > Two like poles repel each other. Two unlike poles attract each other.

> What happens when the poles of two magnets are brought close together? > Two like poles repel each other. Two unlike poles attract each other. CHAPTER OUTLINE Section 1 Magnets and Magnetic Fields Key Idea questions > What happens when the poles of two magnets are brought close together? > What causes a magnet to attract or repel another magnet?

More information

Agenda for Today. Elements of Physics II. Forces on currents

Agenda for Today. Elements of Physics II. Forces on currents Forces on currents Physics 132: Lecture e 14 Elements of Physics II Agenda for Today Currents are moving charges Torque on current loop Torque on rotated loop Currents create B-fields Adding magnetic fields

More information

ELECTROMAGNETIC INDUCTION AND FARADAY S LAW

ELECTROMAGNETIC INDUCTION AND FARADAY S LAW ELECTROMAGNETIC INDUCTION AND FARADAY S LAW Magnetic Flux The emf is actually induced by a change in the quantity called the magnetic flux rather than simply py by a change in the magnetic field Magnetic

More information

Physics 1402: Lecture 18 Today s Agenda

Physics 1402: Lecture 18 Today s Agenda Physics 1402: Lecture 18 Today s Agenda Announcements: Midterm 1 distributed available Homework 05 due Friday Magnetism Calculation of Magnetic Field Two ways to calculate the Magnetic Field: iot-savart

More information

General Physics (PHY 2140)

General Physics (PHY 2140) General Physics (PHY 2140) Lecture 10 6/12/2007 Electricity and Magnetism Induced voltages and induction Self-Inductance RL Circuits Energy in magnetic fields AC circuits and EM waves Resistors, capacitors

More information

Topic 5. Magnetic Induction

Topic 5. Magnetic Induction Topic 5. Magnetic Induction How can a changing magnetic field cause an electric current to flow? Eleven years after the connection between magnetism and electricity was first reported by Oersted, the British

More information

Introduction. First Experiment

Introduction. First Experiment Course : Bsc Applied Physical Science(Computer Science) IInd Year (Semester IV) Paper no : 14 Paper title : Electromagnetic Theory Lecture No : 14 Tittle : Faraday s Law of Induction Introduction Hello

More information

Faraday s Law of Electromagnetic Induction

Faraday s Law of Electromagnetic Induction Faraday s Law of Electromagnetic Induction 2.1 Represent and reason The rectangular loop with a resistor is pulled at constant velocity through a uniform external magnetic field that points into the paper

More information

Name: Class: Date: AP Physics Spring 2012 Q6 Practice. Multiple Choice Identify the choice that best completes the statement or answers the question.

Name: 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 information

Lecture 29: MON 03 NOV

Lecture 29: MON 03 NOV Physics 2113 Jonathan Dowling Lecture 29: MON 03 NOV Ch30.1 4 Induction and Inductance I Fender Stratocaster Solenoid Pickup Magnetic Circuit Breaker As the normal operating or "rated" current flows through

More information

PHYSICS 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 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 information

Chapter 30. Induction and Inductance

Chapter 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 information

Induced Electric Field

Induced Electric Field Lecture 18 Chapter 33 Physics II Induced Electric Field Course website: http://faculty.uml.edu/andriy_danylov/teaching/physicsii Applications of Faraday s Law (some leftovers from the previous class) Applications

More information

Tactics: Evaluating line integrals

Tactics: Evaluating line integrals Tactics: Evaluating line integrals Ampère s law Whenever total current I through passes through an area bounded by a closed curve, the line integral of the magnetic field around the curve is given by Ampère

More information

AP Physics C. Magnetism - Term 4

AP 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 information

Magnetic Induction Faraday, Lenz, Mutual & Self Inductance Maxwell s Eqns, E-M waves. Reading Journals for Tuesday from table(s)

Magnetic 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 information

Physics for Scientists & Engineers 2

Physics for Scientists & Engineers 2 Induction Physics for Scientists & Engineers 2 Spring Semester 2005 Lecture 25! Last week we learned that a current-carrying loop in a magnetic field experiences a torque! If we start with a loop with

More information

Electromagnetic Induction

Electromagnetic Induction 362 Mechanical Engineering Technician UNIT 7 Electromagnetic Induction Structure 7.1 Introduction 7.2 Faraday s laws of Electromagnetic Induction 7.3. Lenz s law 7.4. Fleming s right and rule 7.5. Self

More information

Revision Guide for Chapter 15

Revision Guide for Chapter 15 Revision Guide for Chapter 15 Contents tudent s Checklist Revision otes Transformer... 4 Electromagnetic induction... 4 Generator... 5 Electric motor... 6 Magnetic field... 8 Magnetic flux... 9 Force on

More information

Revision Compare Between. Application

Revision Compare Between. Application evision Compare etween Points of Comparison Series Connection Parallel Connection Drawing otal resistance ( ) = + + 3 3 Potential Difference () = + + 3 = = = 3 Electric Current (I) I = I = I = I 3 I =

More information

Physics 180B Fall 2008 Test Points

Physics 180B Fall 2008 Test Points Physics 180B Fall 2008 Test 2-120 Points Name You can cross off questions or problems worth up to15 points. Circle your answers or pu them in the box provided. 1) The diagram represents a one loop coil

More information

EXPERIMENT 12 OHM S LAW

EXPERIMENT 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 information

Physics 112. Study Notes for Exam II

Physics 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 information

PHY101: Major Concepts in Physics I

PHY101: Major Concepts in Physics I Welcome back to PHY101: Major Concepts in Physics I Photo: J. M. Schwarz Announcements In class today we will finish Chapter 20 (sections 3, 4, and 7). and then move to Chapter 13 (the first six sections).

More information

CHAPTER 5 ELECTROMAGNETIC INDUCTION

CHAPTER 5 ELECTROMAGNETIC INDUCTION CHAPTER 5 ELECTROMAGNETIC INDUCTION 1 Quick Summary on Previous Concepts Electrostatics Magnetostatics Electromagnetic Induction 2 Cases of Changing Magnetic Field Changing Field Strength in a Loop A Loop

More information

Question 6.1: Predict the direction of induced current in the situations described by the following Figs. 6.18(a) to (f ). (a) (b) (c) (d) (e) (f) The direction of the induced current in a closed loop

More information

Unit 8: Electromagnetism

Unit 8: Electromagnetism Multiple Choice Portion Unit 8: Electromagnetism 1. Four compasses are placed around a conductor carrying a current into the page, as shown below. Which compass correctly shows the direction of the magnetic

More information

Problem Solving: Faraday s Law & Inductance. Faraday s Law

Problem Solving: Faraday s Law & Inductance. Faraday s Law MASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Physics: 8.02 Problem Solving: Faraday s Law & Inductance Section Table Names Faraday s Law In Chapter 10 of the 8.02 Course Notes, we have seen that

More information

Magnetic inductance & Solenoids. P.Ravindran, PHY041: Electricity & Magnetism 22 February 2013: Magnetic inductance, and Solenoid

Magnetic inductance & Solenoids. P.Ravindran, PHY041: Electricity & Magnetism 22 February 2013: Magnetic inductance, and Solenoid Magnetic inductance & Solenoids Changing Magnetic Flux A changing magnetic flux in a wire loop induces an electric current. The induced current is always in a direction that opposes the change in flux.

More information

Mansfield 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 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 information

Sliding Conducting Bar

Sliding 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 information

AAST/AEDT. Electromagnetic Induction. If the permanent magnet is at rest, then - there is no current in a coil.

AAST/AEDT. Electromagnetic Induction. If the permanent magnet is at rest, then - there is no current in a coil. 1 AP PHYSICS C AAST/AEDT Electromagnetic Induction Let us run several experiments. 1. A coil with wire is connected with the Galvanometer. If the permanent magnet is at rest, then - there is no current

More information

The Digital Multimeter (DMM)

The Digital Multimeter (DMM) The Digital Multimeter (DMM) Since Physics 152 covers electricity and magnetism, the analysis of both DC and AC circuits is required. In the lab, you will need to measure resistance, potential (voltage),

More information

CHAPTER 5: ELECTROMAGNETIC INDUCTION

CHAPTER 5: ELECTROMAGNETIC INDUCTION CHAPTER 5: ELECTROMAGNETIC INDUCTION PSPM II 2005/2006 NO. 5 5. An AC generator consists a coil of 30 turns with cross sectional area 0.05 m 2 and resistance 100 Ω. The coil rotates in a magnetic field

More information

Topic 6.3 Magnetic Force and Field. 2 hours

Topic 6.3 Magnetic Force and Field. 2 hours Topic 6.3 Magnetic Force and Field 2 hours 1 Magnetic Fields A magnetic field is said to exist at a point if a compass needle placed there experiences a force. The appearance of a magnetic field can be

More information

Induced Electric Field

Induced Electric Field Lecture 20 Chapter 30 Induced Electric Field This fool said some nonsense that the electric field can be produced from the magnetic field. Course website: http://faculty.uml.edu/andriy_danylov/teaching/physicsii

More information

Section 11: Magnetic Fields and Induction (Faraday's Discovery)

Section 11: Magnetic Fields and Induction (Faraday's Discovery) Section 11: Magnetic Fields and Induction (Faraday's Discovery) In this lesson you will describe Faraday's law of electromagnetic induction and tell how it complements Oersted's Principle express an understanding

More information

Revision Guide for Chapter 15

Revision Guide for Chapter 15 Revision Guide for Chapter 15 Contents Revision Checklist Revision otes Transformer...4 Electromagnetic induction...4 Lenz's law...5 Generator...6 Electric motor...7 Magnetic field...9 Magnetic flux...

More information

Induced Electric Field

Induced Electric Field Lecture 18 Chapter 30 Physics II Induced Electric Field Course website: http://faculty.uml.edu/andriy_danylov/teaching/physicsii Today we are going to discuss: Chapter 30: Section 30.5, 30.6 Section 30.7

More information

PHYSICS 30 ELECTROMAGNETISM ASSIGNMENT 3 VERSION:0

PHYSICS 30 ELECTROMAGNETISM ASSIGNMENT 3 VERSION:0 Communication includes statement of the physics concept used and how it is applied in the situation along with diagrams, word explanations and calculations in a well laid out formula, substitution, answer

More information

Chapter 31. Faraday s Law

Chapter 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 information

Section 11: Magnetic Fields and Induction (Faraday's Discovery)

Section 11: Magnetic Fields and Induction (Faraday's Discovery) Section 11: Magnetic Fields and Induction (Faraday's Discovery) In this lesson you will describe Faraday's law of electromagnetic induction and tell how it complements Oersted's Principle express an understanding

More information

Calculus Relationships in AP Physics C: Electricity and Magnetism

Calculus 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 information

3/31/2014. Resistors in series. Resistors in parallel. Ohm s Law. Review for Test 2. Electric Power (cont d) V IR. R constant I

3/31/2014. Resistors in series. Resistors in parallel. Ohm s Law. Review for Test 2. Electric Power (cont d) V IR. R constant I Ohm s Law eview for Test Ohm s law states that the current flowing through a piece of material is proportional to the voltage applied across the material. The resistance () is defined as the ratio of to.

More information