AP Physics C Electricity and Magnetism Syllabus School Vision and Mission Expected School-Wide Learning Results Textbooks Outline

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1 AP Physics C Electricity and Magnetism Syllabus This course fills the second semester of a year-long course in Advanced Placement Physics C. It is a college-level, calculus-based course covering topics in electricity and magnetism. One goal of the course is to develop student s abilities to use physics principles and various mathematical techniques to solve problems in electricity and magnetism. Another goal is to provide college-style lab experiences that foster skills in making observations, forming hypotheses, developing procedures for collecting and analyzing data, and forming conclusions. To this end, there will be five, 3-hour experiments to be done outside of regular school hours. AP Calculus should be taken prior to or concurrent with AP Physics C. Additionally, College Preparatory Physics or AP Physics B should be taken prior to AP Physics C. Students who do not meet these criteria must, along with a parent, sign a waiver. This course is recommended for mathematically deft, hard-working students who plan to attend college and study engineering or physics. School Vision and Mission Our school community believes that education is the cornerstone of a better world. Our mission is to provide an effective, comprehensive education for every student which fosters high academic achievement, positive self-worth, and responsible citizenship in an environment of mutual respect, trust and cooperation among students, staff, and parents. Expected School-Wide Learning Results Our school adopted Expected School-wide Learning Results (ESLRs) as part of the Western Association of Schools and Colleges (WASC) self-study process. The following is the statement of our ESLR s: Our students are well-rounded citizens, innovative and global thinkers, and life-long learners who are respectful of diversity. They communicate effectively by applying information and technology to think critically, and seek skills for the future. Textbooks Kleppner, Daniel, and Norman Ramsey. Quick Calculus: A self-teaching Guide. 2 nd ed. New York: John Wiley and Sons Inc., This text provides some practice with the ideas of differential and integral calculus. Workshop Instructor. AP Physics C Electricity and Magnetism Workbook. Unpublished. This is the primary curriculum for Electricity and Magnetism. All the calculus applications for the course are provided in this workbook. Halliday, David, Robert Resnick, and Jearl Walker. Fundamentals of Physics. 6 th ed. New York: John Wiley & Sons Inc., This serves as a resource text for further explanation of topics and provides an extensive collection of nature s constants, mathematical formulae, and practice problems. Outline The curriculum is divided into eight units covered from mid January to mid April. Students are introduced to the topics by a brief lecture or demonstration followed by reading and problem-solving assignments. This is followed by teacher-driven question-answer sessions and/or student-driven white boarding sessions. Lab experiments are peppered throughout the course to offer a hands-on experience to solidify certain concepts. Calculus is used whenever it can serve as a tool for learning physics. This occurs throughout the course. 1

2 E & M Unit 1 Charged Particles & Electric Fields Chapters 22 & 23 Halliday, Resnick, Walker 1, Coulomb s Law & Electrostatics Definition of Electric Field Determine the work needed to move charges in an electric field Use conservation of energy to calculate the work needed to assemble charges starting at infinity and to calculate the speeds of likecharged particles upon closest approach when fired toward each other from infinity. E & M Unit 2 Electric Fields & Gauss Law Chapters 23 & 24 Halliday, Resnick, Walker Use integration to find the electric field due to a charged infinite wire at distance, d, from the wire Use integration to find the electric field due to a loop of wire along the axis of the loop Use integration to find the electric field due to a disk at a distance, x, from the disk The concept of the flux of a vector field Use Gauss Law to determine the formulae for electric fields of symmetric charge distributions such as infinite lines of charge, infinite flat sheets of charge, cylindrical charge distributions, and spherical charge distributions. E & M Unit 3 Electric Potential Chapter 25 Halliday, Resnick, Walker 1, Electric potential 3 7, Calculate electric potential Equipotentials Electric Field as derivative of potential Summary of ideas covered E & M Unit 4 Capacitors & Dielectrics Chapter 26 Halliday, Resnick, Walker 1, Concept of capacitance Capacitors with planar, cylindrical, and spherical symmetry 4, Equivalent capacitance for capacitors in series and parallel Dielectrics in capacitors 2

3 E & M Unit 5 Ohm s Law & DC Circuits Chapters 27 & 28 Halliday, Resnick, Walker Develop a microscopic model of charge conduction in a metal in terms of drift speed, current, charge, charge density, and cross sectional area Derivation of Ohm s Law, resistivity, and resistance Power related to potential and current , 13 Kirchoff s rules Equivalent resistance for resistors in series and parallel , 19 Electrical Instruments 7, RC circuits E & M Unit 6 Magnetic Forces & Fields Chapter 29 Halliday, Resnick, Walker Applying the right hand rule to determine the direction of the product of two vectors Charged particles in uniform circular motion due to a magnetic field The essential workings of the velocity selector and the mass spectrometer Current-carrying wires in magnetic fields E & M Unit 7 Calculating B-Fields Due to Current Chapter 30 Halliday, Resnick, Walker Introduction to Biot-Savart 2 6, Applying Biot-Savart 3 8, Forces between long straight wires Ampere s law Applying Ampere s Law to determine the magnetic field inside a solenoid and a toroid E & M Unit 8 Electromagnetic Induction Chapter 31 Halliday, Resnick, Walker Magnetic flux and induced EMF Lenz s law 4 17, Faraday s law , 16 Using Faraday s Law, Lenz s Law, and Ohm s Law to determine induced EMF and current Inductance and RL circuits Maxwell s equations are discussed as the culmination of the laws of Gauss, Faraday, and Ampere. The equations reveal the unification of electricity and magnetism. 3

4 Teaching Strategies: Scope and Sequence Lecture and Question/Answer Sessions Students are introduced to the topics either by a brief lecture or a demonstration. Students are encouraged to ask any and all questions they may have when the class period begins. This includes getting clarification on the textbook reading, the lecture notes, and the homework problems. Frequently, students will be asked to pair up and take a moment to discuss concepts. Additionally, students will often be asked to put problems on the board and explain how they arrived at their solution. Each day, students are expected to have read the appropriate pages from the workbook packet and to have tried the homework exercises. Problem Assignments Textbook exercises Some of the assigned exercises were selected on the basis of giving students practice using certain principles of physics to derive formulas. For instance, Gauss law is used to derive the formulas for the electric field in a region of space due to certain symmetric charge distributions. Other exercises involve only a single memorized formula to be used in finding a solution; and even then, the students will know the origin or derivation of the formula. Some class time is used for students to pair up and start their textbook assignments, which often consists of five problems. This allows their progress to be monitored so immediate assistance can be provided and it helps to minimize the frustration level that many students face while attempting to do homework on their own. The next day, the assignments are stamped in order to check for reasonable attempts to solve the problems. Students can then ask that solutions be put on the board either by the instructor or by another student. This is one means of getting students to practice public speaking and it also enhances their understanding of physics. Additionally students can get extra practice at home by doing textbook exercises not assigned or by downloading exercises from the web. Throughout the course, the point will be stressed that memorizing solution recipes is of little value since it is unlikely that a question on the AP Physics C Electricity and Magnetism exam will be exactly like the ones memorized. Lab Experiments Calculation of Laboratory Time The course runs for 18 weeks and meets for 255 minutes per week for a total of 4,590 minutes. There are five 180 minute lab sessions after school for a total of 900 minutes. In addition to the after-school lab time, there are roughly 60 minutes of in-class time per lab dedicated to pre lab and post lab discussions which adds roughly 300 minutes to the lab aspect of the course. The total time dedicated to labs is roughly 26% of state-mandated seat time. Curricular Purpose of Laboratory Investigations The labs are hands-on and provide an opportunity for students to work collaboratively in small groups of three or four. Each student will be expected to keep a lab composition book for all write-ups. Students are given an objective such as: Determine how voltage is related to current. Students are expected to work together to design their own experiment to meet the objective. To this end, students will state the problem, form a hypothesis such as voltage varies directly with current, write a procedure, make observations, take measurements, record data, perform statistical data analysis, and write a conclusion. In writing the procedure, students will make a decision as to which variable to manipulate (independent variable) and which variable changes as a result (dependent variable) and which variables are to remain fixed (control variables). Analysis of the data includes performing calculations, constructing graphs of independent variable vs. dependent variable and writing the appropriate equation of the graph. This can be done by using a graphing calculator, Excel, the LabQuest, and/or Logger Pro. Students then look at the equation and the units of the slope to conclude that the slope must be resistance in the example above. 4

5 The labs will mostly be guided-inquiry which means students investigate a teacher-presented question using student-designed procedures. Generally, you will: Plan in small groups prior to lab day to determine how you will manipulate the equipment to accomplish the goal and how you will process the data. This may involve some initial play with the equipment. Write down your predictions and assumptions. Conduct the experiment and then develop and record your analysis. The analysis should include a discussion of your prior predictions and assumptions as well as possible sources of uncertainty. Present your findings in a written report and be prepared to present to the class for critique. Specifically, you will: be given a question to be tested and then form a hypothesis that answers the question design an investigation which is a plan for collecting the data you need. Here, you will identify the variables including controls, independent, and dependent. follow your procedure to collect and present data to be inserted into a data table. analyze and interpret results such as the meaning of your graphs, how your design could be improved to limit errors, and conclusion. Possible E&M Investigations: 1. Electric Potential and Field mapping: The purpose is to see the relationship between the electric field and the electric potential. Using conducting paper, painted electrodes, and a voltmeter, equipotentials are mapped and the appropriate electric field can be sketched. This provides an excellent visual aid for the relationship between the field and the potential. 2. Direct Current Circuits: The purpose is to introduce the idea of current, potential drop, resistance, power, and energy. Series and parallel circuits are investigated and Ohm s law is derived as a mathematical model for the relationship between current and potential drop. 3. RC Circuits: The purpose is to investigate the intricacies of an RC circuit including the charge voltage and current are measured across the resistor and the capacitor. This data is plotted and a mathematical model is derived which is then compared to the theoretical solution to the differential equations of RC circuits. 4. Lenz s Law: The purpose is to investigate the interesting phenomenon known as Lenz s Law. A current-carrying coil (A) is held next to another coil (B). As the switch on the current in coil A is closed, current is seen to flow in coil B. When the switch remains closed the current in coil B goes to zero since no change in flux is present. When the switch in coil A is opened, the current in coil B starts flowing again but in the opposite direction. Students are directed to come up with their own ways of changing the flux to induce current in coil B. 5. Force on a Current-Carrying Wire: The purpose is to discover which factors affect the attraction or repulsion of two straight, parallel, current-carrying wires separated by a distance. Students discover that the important factors are length, current strength, and separation distance. Evaluation and Grading Formative assessments (quizzes) are given frequently so students can focus on areas of weakness prior to the larger summative unit exams. The unit exams consist of multiple-choice questions (no calculator) and free-response questions (calculator allowed). The multiple-choice questions usually involve the use of a single equation or concept. The free-response questions involve the use of several equations or concepts to solve multipart problems. The same reference tables are used on each exam as those 5

6 provided on the actual AP Physics C Electricity & Magnetism test. Course grades are based on weighted averages between homework, labs, quizzes, and tests. Grades are assigned using the following scale: A (80-100); B ( ); C ( ); D ( ); F ( ). Technology Used by the Students The primary use of technology will be in the laboratory. Students will gather data by using various types of electronic equipment such as Pasco s Xplorer GLX Data Collection Interface, RLC circuits, voltage and current sensors, magnetic field sensors, solenoids, multimeters, power supplies, and power amplifiers. Students will use TI graphing calculators ranging from the 83 up to the 89 model to compute numerical answers to textbook problems as well as to model events such as a decay graph of a discharging capacitor in the laboratory. Students will use computers to access websites that feature Java Applets which simulate physical situations. Additionally, students will use Microsoft Word and Excel to create professional quality lab reports. Technology Used by the Instructor The instructor will use much of the equipment described in the student technology section to perform demonstrations of principles that are otherwise difficult to grasp. The instructor will use Microsoft PowerPoint and Java Applets as an aide in lecturing and delivering curriculum to the students. AP Exam Review Usually we have roughly three weeks to review for the exam. Students are given free-response questions from several of the prior AP exams. These questions are separated by unit such as E-fields or DC circuits. The multiple choice questions from one AP Physics C E&M released exam are also given. Several problems are assigned each day. The first part of each class day is used to answer any questions students may have about the previously assigned problems. With whatever time remains in a period, students are to work independently on free-response questions in 15 minute intervals. They can then check their work against my notebook of solutions. 6