1 of 7 4/13/2010 8:05 PM

Save this PDF as:
 WORD  PNG  TXT  JPG

Size: px
Start display at page:

Download "1 of 7 4/13/2010 8:05 PM"

Transcription

1 Chapter 33 Homework Due: 8:00am on Wednesday, April 7, 2010 Note: To understand how points are awarded, read your instructor's Grading Policy [Return to Standard Assignment View] Canceling a Magnetic Field Four very long, current-carrying wires in the same plane intersect to form a square with side lengths of 460 through the wires are 80, 200, 100, and, as shown in the figure The currents running Find the magnitude of the current that will make the magnetic field at the center of the square equal to zero Hint A1 How to approach the problem Find the magnetic field at the center of the square due to the wires whose current you know Then, find the current wires whose contribution to the magnetic field will exactly cancel the contribution of the other three Hint A2 Calculating the contribution from the three known wires What is the magnitude of the magnetic field at the center of the square due to the wires carrying the 80-, 20-, and 10- currents? Be careful with signs when you add the contributions from the three different wires Hint A21 Ampère's law Recall Ampère's law: You can use this to determine the formula for the magnetic field generated by a long wire Use a circle centered on the wire as your path of integration Hint A22 Getting your signs correct Recall the right-hand rule: If your thumb, on your right hand, points in the direction in which the current is flowing, your fingers will curl in the direction of the magnetic field Express your answer in teslas to three significant figures = Answer Requested Good You should have derived the following equation for the contribution to the magnetic field from one wire:, where is width of the square Use this formula and the fact that you want the magnetic field at the center to sum to zero to find the current Express your answer in amperes = 200 What is the direction of the current? Hint B1 How to approach the problem upward downward Magnetic Field due to Semicircular Wires A loop of wire is in the shape of two concentric semicircles as shown The inner circle has radius ; the outer circle has radius A current flows clockwise through the outer wire and counterclockwise through the inner wire 1 of 7 4/13/2010 8:05 PM

2 2 of 7 4/13/2010 8:05 PM What is the magnitude, Hint A1 Hint A2 Hint A3 Hint A4, of the magnetic field at the center of the semicircles? What physical principle to use Compute the field due to the inner semicircle Direction of the field due to the inner semicircle Compute the field due to the straight wire segments Express in terms of any or all of the following:,,, and = To see whether and makes sense, think of the scaling of different quantities The size of the current element scales as the radius, whereas the power of in the denominator is 2 (and equals the radius also, in this case) So over all, you would expect the magnetic field to scale as 1/radius Note that such an argument works only because the field due to each point is in the same direction, so you are doing a much simpler integral What is the direction of the magnetic field at the center of the semicircles? into the screen out of the screen The magnetic field at the center of a 0600-cm-diameter loop is 250 Problem 3311 What is the current in the loop? 119 A A long straight wire carries the same current you found in part a At what distance from the wire is the magnetic field 250? m A 990 current circulates around a 160-mm-diameter superconducting ring Problem 3316 What is the ring's magnetic dipole moment? What is the on-axis magnetic field strength 540 from the ring? T

3 3 of 7 4/13/2010 8:05 PM Problem 3340 A small bar magnet experiences a torque when the axis of the magnet is at to a 0150 magnetic field What is the magnitude of its magnetic dipole moment? 0198 Problem 3325 Magnetic resonance imaging needs a magnetic field strength of 15 T The solenoid is 18 m long and 75 cm in diameter It is tightly wound with a single layer of 180-mm-diameter superconducting wire What current is needed? 2150 A Magnetic Force on Charged Particles Conceptual Question For each of the situations below, a charged particle enters a region of uniform magnetic field Determine the direction of the force on each charge due to the magnetic field Determine the direction of the force on the charge due to the magnetic field Hint A1 Determining the direction of a magnetic force points into the page points out of the page points neither into nor out of the page and Determine the direction of the force on the charge due to the magnetic field Hint B1 Determining the direction of a magnetic force points out of the page points into the page points neither into nor out of the page and

4 4 of 7 4/13/2010 8:05 PM Part C Determine the direction of the force on the charge due to the magnetic field Note that the charge is negative Hint C1 Effect of a magnetic field on a negative charge points out of the page points into the page points neither into nor out of the page and Problem 3326 A proton moves in the magnetic field with a speed of in the directions shown in the figure For each, what is magnetic force on the proton? Express vector in the form,,, where the x, y, and z components are separated by commas = 0, ,0 N Express vector in the form,,, where the x, y, and z components are separated by commas = 0,0,0 N The aurora is caused when electrons and protons, moving in the earth's magnetic field of Problem 3330, collide with molecules of the atmosphere and cause them to glow What is the radius of the cyclotron orbit for an electron with speed? 0114 m What is the radius of the cyclotron orbit for a proton with speed 104 m

5 5 of 7 4/13/2010 8:05 PM Magnetic Force on a Current-Carrying Wire Learning Goal: To understand the magnetic force on a straight current-carrying wire in a uniform magnetic field Magnetic fields exert forces on moving charged particles, whether those charges are moving independently or are confined to a current-carrying wire The magnetic force on an individual moving charged particle depends on its velocity and charge In the case of a current-carrying wire, many charged particles are simultaneously in motion, so the magnetic force depends on the total current and the length of the wire The size of the magnetic force on a straight wire of length carrying current in a uniform magnetic field with strength is Here is the angle between the direction of the current (along the wire) and the direction of the magnetic field Hence refers to the component of the magnetic field that is perpendicular to the wire, Thus this equation can also be written as The direction of the magnetic force on the wire can be described using a "right-hand rule" This will be discussed after Consider a wire of length = 030 that runs north-south on a horizontal surface There is a current of = 050 flowing north in the wire (The rest of the circuit, which actually delivers this current, is not shown) The Earth's magnetic field at this location has a magnitude of 050 (or, in SI units, ) and points north and 38 degrees down from the horizontal, toward the ground What is the size of the magnetic force on the wire due to the Earth's magnetic field? In considering the agreement of units, recall that Express your answer in newtons to two significant figures Because the Earth's magnetic field is quite modest, this force is so small that it might be hard to detect Now assume that a strong, uniform magnetic field of size 055 magnetic field pointing straight down is applied What is the size of the magnetic force on the wire due to this applied magnetic field? Ignore the effect of the Earth's Hint B1 Determining the angle theta Express your answer in newtons to two significant figures This force would be noticeable if the wire were of light weight The direction of the magnetic force is perpendicular to both the direction of the current flow and the direction of the magnetic field Here is a "right-hand rule" to help you determine the direction of the magnetic force 1 Straighten the fingers of your right hand and point them in the direction of the current 2 Rotate your arm until you can bend your fingers to point in the direction of the magnetic field 3 Your thumb now points in the direction of the magnetic force acting on the wire Part C What is the direction of the magnetic force acting on the wire in due to the applied magnetic field? due north due south due east due west straight up straight down Part D

6 6 of 7 4/13/2010 8:05 PM Which of the following situations would result in a magnetic force on the wire that points due north? Check all that apply Current in the wire flows straight down; the magnetic field points due west Current in the wire flows straight up; the magnetic field points due east Current in the wire flows due east; the magnetic field points straight down Current in the wire flows due west and slightly up; the magnetic field points due east Current in the wire flows due west and slightly down; the magnetic field points straight down As you can see, many current/magnetic field configurations can result in the same direction of magnetic force Part E Assume that the applied magnetic field of size 055 is rotated so that it points horizontally due south What is the size of the magnetic force on the wire due to the applied magnetic field now? Hint E1 Determining the angle theta Recall that is the angle between the magnetic field direction and the direction of the current flow in the wire In this situation, what is the value of? 0 degrees 38 degrees 90 degrees 180 degrees Express your answer in newtons to two significant figures 0 Notice that whenever the current in the wire and the magnetic field point in the same direction ( ) or in opposite directions ( ), the sine of is zero, so there is no magnetic force exerted on the wire This is consistent with the earlier statement that it is the component of the magnetic field that is perpendicular to the direction of the current that produces the magnetic force Also notice that for these two special values of (when the current is flowing parallel to or antiparallel to the magnetic field) the steps listed for the right-hand rule suggest a unique direction for the magnetic force This is another clue that the magnetic force is zero Problem 3336 What is the force on the first wire in the figure? What is the force on the second wire in the figure?

7 7 of 7 4/13/2010 8:05 PM Part C What is the force on the third wire in the figure? Rail Gun A Rail Gun uses electromagnetic forces to accelerate a projectile to very high velocities The basic mechanism of acceleration is relatively simple and can be illustrated in the following example A metal rod of mass and electrical resistance rests on parallel horizontal rails (that have negligible electric resistance), which are a distance apart The rails are also connected to a voltage source, so a current loop is formed The rod begins to move if the externally applied vertical magnetic field in which the rod is located reaches the value flattened bottom so that it slides instead of rolling Use for the magnitude of the acceleration due to gravity Assume that the rod has a slightly Find, the coefficient of static friction between the rod and the rails Hint A1 Hint A2 Hint A3 How to approach this problem Force due to the magnetic field Frictional force Express the coefficient of static friction in terms of variables given in the introduction = Score Summary: Your score on this assignment is 992% You received 7943 out of a possible total of 85 points, plus 485 points of extra credit

Force on Moving Charges in a Magnetic Field

Force on Moving Charges in a Magnetic Field [ Assignment View ] [ Eðlisfræði 2, vor 2007 27. Magnetic Field and Magnetic Forces Assignment is due at 2:00am on Wednesday, February 28, 2007 Credit for problems submitted late will decrease to 0% after

More information

Physics 126 Practice Exam #3 Professor Siegel

Physics 126 Practice Exam #3 Professor Siegel Physics 126 Practice Exam #3 Professor Siegel Name: Lab Day: 1. Which one of the following statements concerning the magnetic force on a charged particle in a magnetic field is true? A) The magnetic force

More information

Magnetism. d. gives the direction of the force on a charge moving in a magnetic field. b. results in negative charges moving. clockwise.

Magnetism. d. gives the direction of the force on a charge moving in a magnetic field. b. results in negative charges moving. clockwise. Magnetism 1. An electron which moves with a speed of 3.0 10 4 m/s parallel to a uniform magnetic field of 0.40 T experiences a force of what magnitude? (e = 1.6 10 19 C) a. 4.8 10 14 N c. 2.2 10 24 N b.

More information

Conceptual: 1, 3, 5, 6, 8, 16, 18, 19. Problems: 4, 6, 8, 11, 16, 20, 23, 27, 34, 41, 45, 56, 60, 65. Conceptual Questions

Conceptual: 1, 3, 5, 6, 8, 16, 18, 19. Problems: 4, 6, 8, 11, 16, 20, 23, 27, 34, 41, 45, 56, 60, 65. Conceptual Questions Conceptual: 1, 3, 5, 6, 8, 16, 18, 19 Problems: 4, 6, 8, 11, 16, 20, 23, 27, 34, 41, 45, 56, 60, 65 Conceptual Questions 1. The magnetic field cannot be described as the magnetic force per unit charge

More information

Eðlisfræði 2, vor 2007

Eðlisfræði 2, vor 2007 [ Assignment View ] [ Pri Eðlisfræði 2, vor 2007 28. Sources of Magnetic Field Assignment is due at 2:00am on Wednesday, March 7, 2007 Credit for problems submitted late will decrease to 0% after the deadline

More information

Fall 12 PHY 122 Homework Solutions #8

Fall 12 PHY 122 Homework Solutions #8 Fall 12 PHY 122 Homework Solutions #8 Chapter 27 Problem 22 An electron moves with velocity v= (7.0i - 6.0j)10 4 m/s in a magnetic field B= (-0.80i + 0.60j)T. Determine the magnitude and direction of the

More information

Physics 1653 Exam 3 - Review Questions

Physics 1653 Exam 3 - Review Questions Physics 1653 Exam 3 - Review Questions 3.0 Two uncharged conducting spheres, A and B, are suspended from insulating threads so that they touch each other. While a negatively charged rod is held near, but

More information

Chapter 19 Magnetic Forces and Fields

Chapter 19 Magnetic Forces and Fields Chapter 19 Magnetic Forces and Fields Student: 3. The magnetism of the Earth acts approximately as if it originates from a huge bar magnet within the Earth. Which of the following statements are true?

More information

Physics 112 Homework 5 (solutions) (2004 Fall) Solutions to Homework Questions 5

Physics 112 Homework 5 (solutions) (2004 Fall) Solutions to Homework Questions 5 Solutions to Homework Questions 5 Chapt19, Problem-2: (a) Find the direction of the force on a proton (a positively charged particle) moving through the magnetic fields in Figure P19.2, as shown. (b) Repeat

More information

1. Units of a magnetic field might be: A. C m/s B. C s/m C. C/kg D. kg/c s E. N/C m ans: D

1. Units of a magnetic field might be: A. C m/s B. C s/m C. C/kg D. kg/c s E. N/C m ans: D Chapter 28: MAGNETIC FIELDS 1 Units of a magnetic field might be: A C m/s B C s/m C C/kg D kg/c s E N/C m 2 In the formula F = q v B: A F must be perpendicular to v but not necessarily to B B F must be

More information

TIME OF COMPLETION DEPARTMENT OF NATURAL SCIENCES. PHYS 2212, Exam 2 Section 1 Version 1 April 16, 2014 Total Weight: 100 points

TIME OF COMPLETION DEPARTMENT OF NATURAL SCIENCES. PHYS 2212, Exam 2 Section 1 Version 1 April 16, 2014 Total Weight: 100 points TIME OF COMPLETION NAME DEPARTMENT OF NATURAL SCIENCES PHYS 2212, Exam 2 Section 1 Version 1 April 16, 2014 Total Weight: 100 points 1. Check your examination for completeness prior to starting. There

More information

Chapter 22 Magnetism

Chapter 22 Magnetism 22.6 Electric Current, Magnetic Fields, and Ampere s Law Chapter 22 Magnetism 22.1 The Magnetic Field 22.2 The Magnetic Force on Moving Charges 22.3 The Motion of Charged particles in a Magnetic Field

More information

Homework #8 203-1-1721 Physics 2 for Students of Mechanical Engineering. Part A

Homework #8 203-1-1721 Physics 2 for Students of Mechanical Engineering. Part A Homework #8 203-1-1721 Physics 2 for Students of Mechanical Engineering Part A 1. Four particles follow the paths shown in Fig. 32-33 below as they pass through the magnetic field there. What can one conclude

More information

Chapter 14 Magnets and

Chapter 14 Magnets and Chapter 14 Magnets and Electromagnetism How do magnets work? What is the Earth s magnetic field? Is the magnetic force similar to the electrostatic force? Magnets and the Magnetic Force! We are generally

More information

Physics 121 Sample Common Exam 3 NOTE: ANSWERS ARE ON PAGE 6. Instructions: 1. In the formula F = qvxb:

Physics 121 Sample Common Exam 3 NOTE: ANSWERS ARE ON PAGE 6. Instructions: 1. In the formula F = qvxb: Physics 121 Sample Common Exam 3 NOTE: ANSWERS ARE ON PAGE 6 Signature Name (Print): 4 Digit ID: Section: Instructions: Answer all questions 24 multiple choice questions. You may need to do some calculation.

More information

physics 112N magnetic fields and forces

physics 112N magnetic fields and forces physics 112N magnetic fields and forces bar magnet & iron filings physics 112N 2 bar magnets physics 112N 3 the Earth s magnetic field physics 112N 4 electro -magnetism! is there a connection between electricity

More information

Chapter 19: Magnetic Forces and Fields

Chapter 19: Magnetic Forces and Fields Chapter 19: Magnetic Forces and Fields Magnetic Fields Magnetic Force on a Point Charge Motion of a Charged Particle in a Magnetic Field Crossed E and B fields Magnetic Forces on Current Carrying Wires

More information

Solution: (a) For a positively charged particle, the direction of the force is that predicted by the right hand rule. These are:

Solution: (a) For a positively charged particle, the direction of the force is that predicted by the right hand rule. These are: Problem 1. (a) Find the direction of the force on a proton (a positively charged particle) moving through the magnetic fields as shown in the figure. (b) Repeat part (a), assuming the moving particle is

More information

Physics 2B. Lecture 29B

Physics 2B. Lecture 29B Physics 2B Lecture 29B "There is a magnet in your heart that will attract true friends. That magnet is unselfishness, thinking of others first. When you learn to live for others, they will live for you."

More information

Review Questions PHYS 2426 Exam 2

Review Questions PHYS 2426 Exam 2 Review Questions PHYS 2426 Exam 2 1. If 4.7 x 10 16 electrons pass a particular point in a wire every second, what is the current in the wire? A) 4.7 ma B) 7.5 A C) 2.9 A D) 7.5 ma E) 0.29 A Ans: D 2.

More information

Module 3 : Electromagnetism Lecture 13 : Magnetic Field

Module 3 : Electromagnetism Lecture 13 : Magnetic Field Module 3 : Electromagnetism Lecture 13 : Magnetic Field Objectives In this lecture you will learn the following Electric current is the source of magnetic field. When a charged particle is placed in an

More information

Phys222 Winter 2012 Quiz 4 Chapters 29-31. Name

Phys222 Winter 2012 Quiz 4 Chapters 29-31. Name Name If you think that no correct answer is provided, give your answer, state your reasoning briefly; append additional sheet of paper if necessary. 1. A particle (q = 5.0 nc, m = 3.0 µg) moves in a region

More information

Physics 2212 GH Quiz #4 Solutions Spring 2015

Physics 2212 GH Quiz #4 Solutions Spring 2015 Physics 1 GH Quiz #4 Solutions Spring 15 Fundamental Charge e = 1.6 1 19 C Mass of an Electron m e = 9.19 1 31 kg Coulomb constant K = 8.988 1 9 N m /C Vacuum Permittivity ϵ = 8.854 1 1 C /N m Earth s

More information

Chapter 30 - Magnetic Fields and Torque. A PowerPoint Presentation by Paul E. Tippens, Professor of Physics Southern Polytechnic State University

Chapter 30 - Magnetic Fields and Torque. A PowerPoint Presentation by Paul E. Tippens, Professor of Physics Southern Polytechnic State University Chapter 30 - Magnetic Fields and Torque A PowerPoint Presentation by Paul E. Tippens, Professor of Physics Southern Polytechnic State University 2007 Objectives: After completing this module, you should

More information

Chapter 21. Magnetic Forces and Magnetic Fields

Chapter 21. Magnetic Forces and Magnetic Fields Chapter 21 Magnetic Forces and Magnetic Fields 21.1 Magnetic Fields The needle of a compass is permanent magnet that has a north magnetic pole (N) at one end and a south magnetic pole (S) at the other.

More information

1. The diagram below represents magnetic lines of force within a region of space.

1. The diagram below represents magnetic lines of force within a region of space. 1. The diagram below represents magnetic lines of force within a region of space. 4. In which diagram below is the magnetic flux density at point P greatest? (1) (3) (2) (4) The magnetic field is strongest

More information

ElectroMagnetic Induction. AP Physics B

ElectroMagnetic Induction. AP Physics B ElectroMagnetic Induction AP Physics B What is E/M Induction? Electromagnetic Induction is the process of using magnetic fields to produce voltage, and in a complete circuit, a current. Michael Faraday

More information

Physics 210 Q ( PHYSICS210BRIDGE ) My Courses Course Settings

Physics 210 Q ( PHYSICS210BRIDGE ) My Courses Course Settings 1 of 16 9/7/2012 1:10 PM Logged in as Julie Alexander, Instructor Help Log Out Physics 210 Q1 2012 ( PHYSICS210BRIDGE ) My Courses Course Settings Course Home Assignments Roster Gradebook Item Library

More information

CHARGE TO MASS RATIO OF THE ELECTRON

CHARGE TO MASS RATIO OF THE ELECTRON CHARGE TO MASS RATIO OF THE ELECTRON In solving many physics problems, it is necessary to use the value of one or more physical constants. Examples are the velocity of light, c, and mass of the electron,

More information

Chapter 33. The Magnetic Field

Chapter 33. The Magnetic Field Chapter 33. The Magnetic Field Digital information is stored on a hard disk as microscopic patches of magnetism. Just what is magnetism? How are magnetic fields created? What are their properties? These

More information

FORCE ON A CURRENT IN A MAGNETIC FIELD

FORCE ON A CURRENT IN A MAGNETIC FIELD 7/16 Force current 1/8 FORCE ON A CURRENT IN A MAGNETIC FIELD PURPOSE: To study the force exerted on an electric current by a magnetic field. BACKGROUND: When an electric charge moves with a velocity v

More information

VIII. Magnetic Fields - Worked Examples

VIII. Magnetic Fields - Worked Examples MASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Physics 8.0 Spring 003 VIII. Magnetic Fields - Worked Examples Example : Rolling rod A rod with a mass m and a radius R is mounted on two parallel rails

More information

General Physics (PHY 2140)

General Physics (PHY 2140) General Physics (PHY 2140) Lecture 12 Electricity and Magnetism Magnetism Magnetic fields and force Application of magnetic forces http://www.physics.wayne.edu/~apetrov/phy2140/ Chapter 19 1 Department

More information

E/M Experiment: Electrons in a Magnetic Field.

E/M Experiment: Electrons in a Magnetic Field. E/M Experiment: Electrons in a Magnetic Field. PRE-LAB You will be doing this experiment before we cover the relevant material in class. But there are only two fundamental concepts that you need to understand.

More information

Magnetism: a new force!

Magnetism: a new force! -1 Magnetism: a new force! So far, we'e learned about two forces: graity and the electric field force. =, = Definition of -field kq -fields are created by charges: = r -field exerts a force on other charges:

More information

Physics 9 Fall 2009 Homework 7 - Solutions

Physics 9 Fall 2009 Homework 7 - Solutions Physics 9 Fall 009 Homework 7 - s 1. Chapter 33 - Exercise 10. At what distance on the axis of a current loop is the magnetic field half the strength of the field at the center of the loop? Give your answer

More information

My lecture slides are posted at Information for Physics 112 midterm, Wednesday, May 2

My lecture slides are posted at  Information for Physics 112 midterm, Wednesday, May 2 My lecture slides are posted at http://www.physics.ohio-state.edu/~humanic/ Information for Physics 112 midterm, Wednesday, May 2 1) Format: 10 multiple choice questions (each worth 5 points) and two show-work

More information

IMPORTANT NOTE ABOUT WEBASSIGN:

IMPORTANT NOTE ABOUT WEBASSIGN: Week 8 homework IMPORTANT NOTE ABOUT WEBASSIGN: In the WebAssign versions of these problems, various details have been changed, so that the answers will come out differently. The method to find the solution

More information

CET Moving Charges & Magnetism

CET Moving Charges & Magnetism CET 2014 Moving Charges & Magnetism 1. When a charged particle moves perpendicular to the direction of uniform magnetic field its a) energy changes. b) momentum changes. c) both energy and momentum

More information

Copyright 2011 Casa Software Ltd. www.casaxps.com. Centre of Mass

Copyright 2011 Casa Software Ltd. www.casaxps.com. Centre of Mass Centre of Mass A central theme in mathematical modelling is that of reducing complex problems to simpler, and hopefully, equivalent problems for which mathematical analysis is possible. The concept of

More information

1. A wire carries 15 A. You form the wire into a single-turn circular loop with magnetic field 80 µ T at the loop center. What is the loop radius?

1. A wire carries 15 A. You form the wire into a single-turn circular loop with magnetic field 80 µ T at the loop center. What is the loop radius? CHAPTER 3 SOURCES O THE MAGNETC ELD 1. A wire carries 15 A. You form the wire into a single-turn circular loop with magnetic field 8 µ T at the loop center. What is the loop radius? Equation 3-3, with

More information

Magnetic Field and Magnetic Forces

Magnetic Field and Magnetic Forces Chapter 27 Magnetic Field and Magnetic Forces PowerPoint Lectures for University Physics, Thirteenth Edition Hugh D. Young and Roger A. Freedman Lectures by Wayne Anderson Goals for Chapter 27 Magnets

More information

Question Details C14: Magnetic Field Direction Abbott [ ]

Question Details C14: Magnetic Field Direction Abbott [ ] Phys 1114: Assignment 9 Abbott (5420633) Due: Mon Apr 7 2014 11:59 PM CDT Question 1 2 3 4 5 6 7 8 9 10 11 1. Question Details C14: Magnetic Field Direction Abbott [2861537] a) A wire is oriented horizontally

More information

PS-6.2 Explain the factors that determine potential and kinetic energy and the transformation of one to the other.

PS-6.2 Explain the factors that determine potential and kinetic energy and the transformation of one to the other. PS-6.1 Explain how the law of conservation of energy applies to the transformation of various forms of energy (including mechanical energy, electrical energy, chemical energy, light energy, sound energy,

More information

The purposes of this experiment are to test Faraday's Law qualitatively and to test Lenz's Law.

The purposes of this experiment are to test Faraday's Law qualitatively and to test Lenz's Law. 260 17-1 I. THEORY EXPERIMENT 17 QUALITATIVE STUDY OF INDUCED EMF Along the extended central axis of a bar magnet, the magnetic field vector B r, on the side nearer the North pole, points away from this

More information

Magnetism, a history. Existence of a Magnetic Field, B. Magnetic Force on a charged particle. The particle in the figure

Magnetism, a history. Existence of a Magnetic Field, B. Magnetic Force on a charged particle. The particle in the figure Existence of a Magnetic Field, B Magnetic field, B, is a vector You may be familiar with bar magnets have a magnetic field similar to electric field of dipoles Amazing experimental finding: there is a

More information

Force on a square loop of current in a uniform B-field.

Force on a square loop of current in a uniform B-field. Force on a square loop of current in a uniform B-field. F top = 0 θ = 0; sinθ = 0; so F B = 0 F bottom = 0 F left = I a B (out of page) F right = I a B (into page) Assume loop is on a frictionless axis

More information

Multiple Choice Questions for Physics 1 BA113 Chapter 23 Electric Fields

Multiple Choice Questions for Physics 1 BA113 Chapter 23 Electric Fields Multiple Choice Questions for Physics 1 BA113 Chapter 23 Electric Fields 63 When a positive charge q is placed in the field created by two other charges Q 1 and Q 2, each a distance r away from q, the

More information

Pre-lab Quiz/PHYS 224 Magnetic Force and Current Balance. Your name Lab section

Pre-lab Quiz/PHYS 224 Magnetic Force and Current Balance. Your name Lab section Pre-lab Quiz/PHYS 224 Magnetic Force and Current Balance Your name Lab section 1. What do you investigate in this lab? 2. Two straight wires are in parallel and carry electric currents in opposite directions

More information

The DC Motor. Physics 1051 Laboratory #5 The DC Motor

The DC Motor. Physics 1051 Laboratory #5 The DC Motor The DC Motor Physics 1051 Laboratory #5 The DC Motor Contents Part I: Objective Part II: Introduction Magnetic Force Right Hand Rule Force on a Loop Magnetic Dipole Moment Torque Part II: Predictions Force

More information

Name: Date: Regents Physics Mr. Morgante UNIT 4B Magnetism

Name: Date: Regents Physics Mr. Morgante UNIT 4B Magnetism Name: Regents Physics Date: Mr. Morgante UNIT 4B Magnetism Magnetism -Magnetic Force exists b/w charges in motion. -Similar to electric fields, an X stands for a magnetic field line going into the page,

More information

PHY121 #8 Midterm I 3.06.2013

PHY121 #8 Midterm I 3.06.2013 PHY11 #8 Midterm I 3.06.013 AP Physics- Newton s Laws AP Exam Multiple Choice Questions #1 #4 1. When the frictionless system shown above is accelerated by an applied force of magnitude F, the tension

More information

Chapter 8: Magnetism

Chapter 8: Magnetism 8.1 The Force on a Charge in a Magnetic Field - The Definition of the Magnetic Field esides the existence of electric fields in nature, there are also magnetic fields. Most students have seen and played

More information

AP2 Magnetism. (c) Explain why the magnetic field does no work on the particle as it moves in its circular path.

AP2 Magnetism. (c) Explain why the magnetic field does no work on the particle as it moves in its circular path. A charged particle is projected from point P with velocity v at a right angle to a uniform magnetic field directed out of the plane of the page as shown. The particle moves along a circle of radius R.

More information

Physics 9 Fall 2009 Homework 2 - Solutions

Physics 9 Fall 2009 Homework 2 - Solutions Physics 9 Fall 009 Homework - s 1. Chapter 7 - Exercise 5. An electric dipole is formed from ±1.0 nc charges spread.0 mm apart. The dipole is at the origin, oriented along the y axis. What is the electric

More information

Chapter 27 Magnetic Field and Magnetic Forces

Chapter 27 Magnetic Field and Magnetic Forces Chapter 27 Magnetic Field and Magnetic Forces - Magnetism - Magnetic Field - Magnetic Field Lines and Magnetic Flux - Motion of Charged Particles in a Magnetic Field - Applications of Motion of Charged

More information

104 Practice Exam 2-3/21/02

104 Practice Exam 2-3/21/02 104 Practice Exam 2-3/21/02 1. Two electrons are located in a region of space where the magnetic field is zero. Electron A is at rest; and electron B is moving westward with a constant velocity. A non-zero

More information

Chapter 24 Practice Problems, Review, and Assessment

Chapter 24 Practice Problems, Review, and Assessment Section 1 Understanding Magnetism: Practice Problems 1. If you hold a bar magnet in each hand and bring your hands close together, will the force be attractive or repulsive if the magnets are held in the

More information

Magnetic Field & Right Hand Rule. Academic Resource Center

Magnetic Field & Right Hand Rule. Academic Resource Center Magnetic Field & Right Hand Rule Academic Resource Center Magnetic Fields And Right Hand Rules By: Anthony Ruth Magnetic Fields vs Electric Fields Magnetic fields are similar to electric fields, but they

More information

Physics 30 Worksheet #10 : Magnetism From Electricity

Physics 30 Worksheet #10 : Magnetism From Electricity Physics 30 Worksheet #10 : Magnetism From Electricity 1. Draw the magnetic field surrounding the wire showing electron current below. x 2. Draw the magnetic field surrounding the wire showing electron

More information

Section V.4: Cross Product

Section V.4: Cross Product Section V.4: Cross Product Definition The cross product of vectors A and B is written as A B. The result of the cross product A B is a third vector which is perpendicular to both A and B. (Because the

More information

Q28.1 A positive point charge is moving to the right. The magnetic field that the point charge produces at point P (see diagram below) P

Q28.1 A positive point charge is moving to the right. The magnetic field that the point charge produces at point P (see diagram below) P Q28.1 A positive point charge is moving to the right. The magnetic field that the point charge produces at point P (see diagram below) P r + v r A. points in the same direction as v. B. points from point

More information

Last Name: First Name: Physics 102 Spring 2006: Exam #2 Multiple-Choice Questions 1. A charged particle, q, is moving with speed v perpendicular to a uniform magnetic field. A second identical charged

More information

1 of 7 9/5/2009 6:12 PM

1 of 7 9/5/2009 6:12 PM 1 of 7 9/5/2009 6:12 PM Chapter 2 Homework Due: 9:00am on Tuesday, September 8, 2009 Note: To understand how points are awarded, read your instructor's Grading Policy. [Return to Standard Assignment View]

More information

CHAPTER 6 WORK AND ENERGY

CHAPTER 6 WORK AND ENERGY CHAPTER 6 WORK AND ENERGY CONCEPTUAL QUESTIONS. REASONING AND SOLUTION The work done by F in moving the box through a displacement s is W = ( F cos 0 ) s= Fs. The work done by F is W = ( F cos θ). s From

More information

Profs. A. Petkova, A. Rinzler, S. Hershfield. Exam 2 Solution

Profs. A. Petkova, A. Rinzler, S. Hershfield. Exam 2 Solution PHY2049 Fall 2009 Profs. A. Petkova, A. Rinzler, S. Hershfield Exam 2 Solution 1. Three capacitor networks labeled A, B & C are shown in the figure with the individual capacitor values labeled (all units

More information

Physics 1A Lecture 10C

Physics 1A Lecture 10C Physics 1A Lecture 10C "If you neglect to recharge a battery, it dies. And if you run full speed ahead without stopping for water, you lose momentum to finish the race. --Oprah Winfrey Static Equilibrium

More information

) 0.7 =1.58 10 2 N m.

) 0.7 =1.58 10 2 N m. Exam 2 Solutions Prof. Paul Avery Prof. Andrey Korytov Oct. 29, 2014 1. A loop of wire carrying a current of 2.0 A is in the shape of a right triangle with two equal sides, each with length L = 15 cm as

More information

Chapter 18 Electric Forces and Electric Fields. Key Concepts:

Chapter 18 Electric Forces and Electric Fields. Key Concepts: Chapter 18 Lectures Monday, January 25, 2010 7:33 AM Chapter 18 Electric Forces and Electric Fields Key Concepts: electric charge principle of conservation of charge charge polarization, both permanent

More information

Sample Questions for the AP Physics 1 Exam

Sample Questions for the AP Physics 1 Exam Sample Questions for the AP Physics 1 Exam Sample Questions for the AP Physics 1 Exam Multiple-choice Questions Note: To simplify calculations, you may use g 5 10 m/s 2 in all problems. Directions: Each

More information

Faraday s Law of Induction

Faraday s Law of Induction Chapter 10 Faraday s Law of Induction 10.1 Faraday s Law of Induction...10-10.1.1 Magnetic Flux...10-3 10.1. Lenz s Law...10-5 10. Motional EMF...10-7 10.3 Induced Electric Field...10-10 10.4 Generators...10-1

More information

University of California, Berkeley Physics H7B Spring 1999 (Strovink) SOLUTION TO PROBLEM SET 10 Solutions by P. Pebler

University of California, Berkeley Physics H7B Spring 1999 (Strovink) SOLUTION TO PROBLEM SET 10 Solutions by P. Pebler University of California, Berkeley Physics H7B Spring 1999 (Strovink) SOLUTION TO PROBLEM SET 10 Solutions by P Pebler 1 Purcell 66 A round wire of radius r o carries a current I distributed uniformly

More information

Experiment #8: Magnetic Forces

Experiment #8: Magnetic Forces Experiment #8: Magnetic Forces Purpose: To study the nature of magnetic forces exerted on currents. Equipment: Magnet Assembly and Stand Set of Current Loop PC oards Triple-Arm Pan alance 0 15 V dc Variable

More information

Problem Solving 5: Magnetic Force, Torque, and Magnetic Moments

Problem Solving 5: Magnetic Force, Torque, and Magnetic Moments MASSACHUSETTS INSTITUTE OF TECHNOLOY Department of Physics Problem Solving 5: Magnetic Force, Torque, and Magnetic Moments OBJECTIVES 1. To start with the magnetic force on a moving charge q and derive

More information

If you put the same book on a tilted surface the normal force will be less. The magnitude of the normal force will equal: N = W cos θ

If you put the same book on a tilted surface the normal force will be less. The magnitude of the normal force will equal: N = W cos θ Experiment 4 ormal and Frictional Forces Preparation Prepare for this week's quiz by reviewing last week's experiment Read this week's experiment and the section in your textbook dealing with normal forces

More information

Chapter 20. Magnetic Induction Changing Magnetic Fields yield Changing Electric Fields

Chapter 20. Magnetic Induction Changing Magnetic Fields yield Changing Electric Fields Chapter 20 Magnetic Induction Changing Magnetic Fields yield Changing Electric Fields Introduction The motion of a magnet can induce current in practical ways. If a credit card has a magnet strip on its

More information

Physics 2A, Sec B00: Mechanics -- Winter 2011 Instructor: B. Grinstein Final Exam

Physics 2A, Sec B00: Mechanics -- Winter 2011 Instructor: B. Grinstein Final Exam Physics 2A, Sec B00: Mechanics -- Winter 2011 Instructor: B. Grinstein Final Exam INSTRUCTIONS: Use a pencil #2 to fill your scantron. Write your code number and bubble it in under "EXAM NUMBER;" an entry

More information

1) Magnetic field lines come out of the south pole of a magnet and enter at the north pole.

1) Magnetic field lines come out of the south pole of a magnet and enter at the north pole. Exam Name 1) Magnetic field lines come out of the south pole of a magnet and enter at the north pole. 2) Which of the following statements is correct? A) Earth's north pole is magnetic north. B) The north

More information

Exam 2 Solutions. PHY2054 Spring Prof. P. Kumar Prof. P. Avery March 5, 2008

Exam 2 Solutions. PHY2054 Spring Prof. P. Kumar Prof. P. Avery March 5, 2008 Prof. P. Kumar Prof. P. Avery March 5, 008 Exam Solutions 1. Two cylindrical resistors are made of the same material and have the same resistance. The resistors, R 1 and R, have different radii, r 1 and

More information

Date: Deflection of an Electron in a Magnetic Field

Date: Deflection of an Electron in a Magnetic Field Name: Partners: Date: Deflection of an Electron in a Magnetic Field Purpose In this lab, we use a Cathode Ray Tube (CRT) to measure the effects of an electric and magnetic field on the motion of a charged

More information

Magnetic fields of charged particles in motion

Magnetic fields of charged particles in motion C H A P T E R 8 Magnetic fields of charged particles in motion CONCEPTS 8.1 Source of the magnetic field 8. Current loops and spin magnetism 8.3 Magnetic moment and torque 8.4 Ampèrian paths QUANTTATVE

More information

Magnets and the Magnetic Force

Magnets and the Magnetic Force Magnets and the Magnetic Force We are generally more familiar with magnetic forces than with electrostatic forces. Like the gravitational force and the electrostatic force, this force acts even when the

More information

* Biot Savart s Law- Statement, Proof Applications of Biot Savart s Law * Magnetic Field Intensity H * Divergence of B * Curl of B. PPT No.

* Biot Savart s Law- Statement, Proof Applications of Biot Savart s Law * Magnetic Field Intensity H * Divergence of B * Curl of B. PPT No. * Biot Savart s Law- Statement, Proof Applications of Biot Savart s Law * Magnetic Field Intensity H * Divergence of B * Curl of B PPT No. 17 Biot Savart s Law A straight infinitely long wire is carrying

More information

At the skate park on the ramp

At the skate park on the ramp At the skate park on the ramp 1 On the ramp When a cart rolls down a ramp, it begins at rest, but starts moving downward upon release covers more distance each second When a cart rolls up a ramp, it rises

More information

Newton s Laws of Motion

Newton s Laws of Motion Section 3.2 Newton s Laws of Motion Objectives Analyze relationships between forces and motion Calculate the effects of forces on objects Identify force pairs between objects New Vocabulary Newton s first

More information

1 of 10 11/23/2009 6:37 PM

1 of 10 11/23/2009 6:37 PM hapter 14 Homework Due: 9:00am on Thursday November 19 2009 Note: To understand how points are awarded read your instructor's Grading Policy. [Return to Standard Assignment View] Good Vibes: Introduction

More information

Lab 9 Magnetic Interactions

Lab 9 Magnetic Interactions Lab 9 Magnetic nteractions Physics 6 Lab What You Need To Know: The Physics Electricity and magnetism are intrinsically linked and not separate phenomena. Most of the electrical devices you will encounter

More information

F N A) 330 N 0.31 B) 310 N 0.33 C) 250 N 0.27 D) 290 N 0.30 E) 370 N 0.26

F N A) 330 N 0.31 B) 310 N 0.33 C) 250 N 0.27 D) 290 N 0.30 E) 370 N 0.26 Physics 23 Exam 2 Spring 2010 Dr. Alward Page 1 1. A 250-N force is directed horizontally as shown to push a 29-kg box up an inclined plane at a constant speed. Determine the magnitude of the normal force,

More information

Magnetic Fields. I. Magnetic Field and Magnetic Field Lines

Magnetic Fields. I. Magnetic Field and Magnetic Field Lines Magnetic Fields I. Magnetic Field and Magnetic Field Lines A. The concept of the magnetic field can be developed in a manner similar to the way we developed the electric field. The magnitude of the magnetic

More information

LAB 8: Electron Charge-to-Mass Ratio

LAB 8: Electron Charge-to-Mass Ratio Name Date Partner(s) OBJECTIVES LAB 8: Electron Charge-to-Mass Ratio To understand how electric and magnetic fields impact an electron beam To experimentally determine the electron charge-to-mass ratio.

More information

Chapter 22: Electric motors and electromagnetic induction

Chapter 22: Electric motors and electromagnetic induction Chapter 22: Electric motors and electromagnetic induction The motor effect movement from electricity When a current is passed through a wire placed in a magnetic field a force is produced which acts on

More information

VELOCITY, ACCELERATION, FORCE

VELOCITY, ACCELERATION, FORCE VELOCITY, ACCELERATION, FORCE velocity Velocity v is a vector, with units of meters per second ( m s ). Velocity indicates the rate of change of the object s position ( r ); i.e., velocity tells you how

More information

Physics 9 Fall 2009 Homework 8 - Solutions

Physics 9 Fall 2009 Homework 8 - Solutions 1. Chapter 34 - Exercise 9. Physics 9 Fall 2009 Homework 8 - s The current in the solenoid in the figure is increasing. The solenoid is surrounded by a conducting loop. Is there a current in the loop?

More information

B) 40.8 m C) 19.6 m D) None of the other choices is correct. Answer: B

B) 40.8 m C) 19.6 m D) None of the other choices is correct. Answer: B Practice Test 1 1) Abby throws a ball straight up and times it. She sees that the ball goes by the top of a flagpole after 0.60 s and reaches the level of the top of the pole after a total elapsed time

More information

Lab 7: Rotational Motion

Lab 7: Rotational Motion Lab 7: Rotational Motion Equipment: DataStudio, rotary motion sensor mounted on 80 cm rod and heavy duty bench clamp (PASCO ME-9472), string with loop at one end and small white bead at the other end (125

More information

Chapter 11 Equilibrium

Chapter 11 Equilibrium 11.1 The First Condition of Equilibrium The first condition of equilibrium deals with the forces that cause possible translations of a body. The simplest way to define the translational equilibrium of

More information

Chapter 10 Rotational Motion. Copyright 2009 Pearson Education, Inc.

Chapter 10 Rotational Motion. Copyright 2009 Pearson Education, Inc. Chapter 10 Rotational Motion Angular Quantities Units of Chapter 10 Vector Nature of Angular Quantities Constant Angular Acceleration Torque Rotational Dynamics; Torque and Rotational Inertia Solving Problems

More information

Newton s Laws. Physics 1425 lecture 6. Michael Fowler, UVa.

Newton s Laws. Physics 1425 lecture 6. Michael Fowler, UVa. Newton s Laws Physics 1425 lecture 6 Michael Fowler, UVa. Newton Extended Galileo s Picture of Galileo said: Motion to Include Forces Natural horizontal motion is at constant velocity unless a force acts:

More information

Chapter 4. Forces and Newton s Laws of Motion. continued

Chapter 4. Forces and Newton s Laws of Motion. continued Chapter 4 Forces and Newton s Laws of Motion continued 4.9 Static and Kinetic Frictional Forces When an object is in contact with a surface forces can act on the objects. The component of this force acting

More information

11. Sources of Magnetic Fields

11. Sources of Magnetic Fields 11. Sources of Magnetic Fields S. G. Rajeev February 24, 2009 1 Magnetic Field Due to a Straight Wire We saw that electric currents produce magnetic fields. The simplest situation is an infinitely long,

More information