Phys270

Sections 0301, 0302, 0303, 0304 and 0306

 

Spring 2009

 


Electrodynamics, Light, Relativity and Modern Physics

 

Homework Assignments:

Hw1--Due at the 10:00 a.m., Friday, February 6.  The homework should be placed in the appropriate envelope outside Tom Cohen’s office (2104 Physics).   Use the envelope labeled by your section. in class.  In addition there is a Mastering Physics assignment due on Feb 6

 

Hw2--Due at the 10:00 a.m., Friday, February 13.  The homework should be placed in the appropriate envelope outside Tom Cohen’s office (2104 Physics).   Use the envelope labeled by your section. in class.  In addition there is a Mastering Physics assignment due on Feb 13

 

Hw3--Due at the 10:00 a.m., Friday, February 20.  The homework should be placed in the appropriate envelope outside Tom Cohen’s office (2104 Physics).   Use the envelope labeled by your section. in class.  In addition there is a Mastering Physics assignment due on Feb 20

 

Hw4--Due at the 10:00 a.m., Friday, February 27.  The homework should be placed in the appropriate envelope outside Tom Cohen’s office (2104 Physics).   Use the envelope labeled by your section. in class.  In addition there is a Mastering Physics assignment due on Feb 27

 

 

Hw5--Due at the 10:00 a.m., Friday, March 6.  The homework should be placed in the appropriate envelope outside Tom Cohen’s office (2104 Physics).   Use the envelope labeled by your section. in class.  In addition there is a Mastering Physics assignment due on March 6

 

 

Hw6--Due at the 10:00 a.m., Friday, March 13.  The homework should be placed in the appropriate envelope outside Tom Cohen’s office (2104 Physics).   Use the envelope labeled by your section. in class.  In addition there is a Mastering Physics assignment due on March 13

 

Hw7--Due at the 10:00 a.m., Friday, March 27.  The homework should be placed in the appropriate envelope outside Tom Cohen’s office (2104 Physics).   Use the envelope labeled by your section. in class.  In addition there is a Mastering Physics assignment due on March 27

 

Hw8--Due at the 10:00 a.m., Friday, April 3.  The homework should be placed in the appropriate envelope outside Tom Cohen’s office (2104 Physics).   Use the envelope labeled by your section. in class.  In addition there is a Mastering Physics assignment due on April 3

 

Hw9--Due at the 10:00 a.m., Friday, April 10.  The homework should be placed in the appropriate envelope outside Tom Cohen’s office (2104 Physics).   Use the envelope labeled by your section. in class.  In addition there is a Mastering Physics assignment due on April 3

 

 

Hw10--Due at the 10:00 a.m., Friday, April 17.  The homework should be placed in the appropriate envelope outside Tom Cohen’s office (2104 Physics).   Use the envelope labeled by your section. in class.  In addition there is a Mastering Physics assignment due on April 17

 

Hw11--Due at the 10:00 a.m., Friday, April 24.  The homework should be placed in the appropriate envelope outside Tom Cohen’s office (2104 Physics).   Use the envelope labeled by your section. in class.  In addition there is a Mastering Physics assignment due on April 24

 

Hw12--Due at 10:00 a.m., Friday, May1.  The homework should be placed in the appropriate envelope outside Tom Cohen’s office (2104 Physics).   Use the envelope labeled by your section. in class.  In addition there is a Mastering Physics assignment due on May 1

 

 

Hw13--Due at 10:00 a.m., Friday, May8.  The homework should be placed in the appropriate envelope outside Tom Cohen’s office (2104 Physics).   Use the envelope labeled by your section. in class.  In addition there is a Mastering Physics assignment due on May 18

 

 

Homework Solutions:

None at present

 



Lecture: Tue, Thus 2:00-3:15 PHY 1412

Instructor: Tom Cohen         (I prefer to be called by my first name)


Room: 2104, Toll Physics Building

 Phone: 5-6117
E-mail:  cohenl@physics.umd.edu

 


Formal Office Hours:       Immediately following lecture Tuesdays and Thursdays

However you should feel free to drop in at his office at other times;

unless he is busy he will be happy to meet with you;

Alternatively you may send e-mail to request an appointment.

 

 

 

Discussion sections:            Section 0301  Thurs. 8:00 am  PHY 4220
Section 0302  Thurs. 3:30 pm  PHY 1402
Section 0303  Mon.   1:00 pm  PHY 4208

Section 0304  Thurs. 11:00 am PHY 4220

Section 0306  Weds. 1:00 p.m. PHY 4208   

 

 

Teaching Assistants:       Ed Behn                                                    Sylvia Zhu

                                                            Sections:   0301 ,0302, 0303, 0306                  Section:   0304

Office:    Physics 0104                                      Office:  Physics 3103B

Phone:   5-8577                                               Phone:  5-6189

e-mail:    ed@behn.us                                       e-mail:  sjzhu@umd.edu

 

 

 

Mandatory Laboratory Requirement :

 

PHYS 271 is the laboratory component of this course. You must complete and pass PHYS271(which requires completing all of the labs) in order to pass PHYS270. PHYS271 must be taken in the same semester in order to count for the CORE Lab Science requirement. PHYS270 taken alone is not accepted as a non-lab science course for CORE. Note: A single grade combined grade is given for PHYS270/PHYS271

 

Mastering Physics


Much of the homework for this course will be assigned through the computer using the “Mastering Physics” system.  You are required to have a Mastering Physics account linked to this course.  When registering, the “Course ID ” is  


The course will cover Chapters 22-24 and 33-41 of Knight (2nd  edition).

 

 

General course information

General Philosophy:  Many students view physics entirely through the prism of problem solving.  From this perspective, a physics course is essentially a set of prescriptions needed to solve certain classes of problems.  This view is unfortunate---the essence of physics is that nature can be understood through a comparative small number of rules which can formulated mathematically.  Some of these laws are empirical in nature: they succinctly encode the results of numerous experiments.  Others of these rules are derived---they can be obtained using mathematical and physical reasoning starting from the empirical laws. Similarly physical laws typically have limited domains of validity and it is essential to understand what they are.  Often this possible only if one has a firm grasp on the origins of the laws in question.  Thus, in this course along with problem solving there will be a strong emphasis on the underlying unity of the physics, the origins of the physical laws used in problem solving, and the use of appropriate mathematical tools for the subject covered. 

Topics:  This course will cover magnetism, electromagnetic induction, Maxwell’s equations and electromagnetic waves, optics (physical and geometric), aspects of “modern physics” (relativity, quantum phenomenon and the composition of matter. )

Book: Physics for Scientists and Engineers: A Strategic Approach 2nd edition, by Randall D. Knight,.  DO NOT PURCHASE THE First EDITION!  The second edition is being phased in for Phys 161, however this course is a continuation of course using the old edition.  .   Note that this course will cover Chapters 22-24 and 33-41 of Knight. It is possible to get this book either in a single volume (as above) or in split into five volumes.  Note if you choose the latter option you will need to have access Volumes 3,4 & 5.Note also that it is possible to purchase the book bundled with “Mastering Physics” and it is to your financial advantage to do so.

Frankly, it is my view that the book has many weaknesses; in particular it does a rather poor job in explaining the origin of many of the physical ideas.  In addition for several topics the book does not use the appropriate mathematical tools to deal with the issues treated.  Accordingly one should NOT view the course and the textbook as being essentially equivalent.

Lecture: As noted above, the book has weaknesses.   The material discussed in lecture will treat essentially same material as in the text but often from a rather different perspective.  It is essential to follow the lectures to do well in the course.  Material for exams will follow the lectures as much or more than the book.

Communication:  I strongly encourage students to make use of e-mail for quick correspondence with me regarding lecture material, homework problems, and the like. I will also use e-mail to communicate with the class at large.

Homework: Homework will generally be assigned weekly with the assignments.  There will be two kinds of assignments:  One type will be assigned through the “Mastering Physics” program and will be graded electronically.  You will be assigned several such problems each week.    The MP assignments will be due on the Friday of the week following their assignment.  This will ensure that all sections will have met prior to the due date and thus give you a chance to ask questions about the assignments.   The other type of problem will be a single problem which you will be expected to work through and write up the solution in a cogent manner.  One purpose of this second type of homework assignment is so that you get some practice in scientific communication---thus you will be expected to explain your reasoning; simply writing down equations is not sufficient. The written assignments will be will due in class  the week following their assignment.  This arrangement will give you a chance to discuss the pending assignment in section before it is due.   

Although you will have many more of the “Mastering Physics” problems then the written ones, each type will count an equal weight in the final grade.  All homework assignments count.  Late homework will not be accepted since solutions will be posted. If there is a legitimate excuse for missing a homework assignment, the average of your other homework grades will be used as a replacememtn of the grade for that assignment.  The Mastering Physics assignments will have a penalty of 20% off for everyday late.

Homework solutions for the written assignments will be posted on the course Web site.  These may simply be scans of correct and well written solutions turned in by students (with the name omitted).  If for some reason you do NOT wish your solution to be placed on the web site please indicate this on your solutions

Mastering Physics Assignments:

You will be allowed six tries to successfully complete each problem and will receive instant feedback on errors.  Some errors may be due to using the incorrect number of significant figures. The on-line homework will use random numerical values so you will have different values from others. It means that you have to understand the correct method of getting the answer in order to succeed. It is important first to work out a formula for the desired quantity so that you develop skills that will help to prepare you for exams. Only after you have thought through the physics and derived an algebraic formula for the result should you plug in numbers.   Mastering Physics sometimes offers hints when you are stuck.  Ideally you should work through the problems without the hints.  To discourage you from going to the hints too easily a modest deduction from the question score will be made when you call a hint. The Mastering Physics assignments will have a penalty of 20% off for everyday late.

The Mastering Physics Access Code is good for two years. Normally, students who obtained an access code when they took Physics 161 will not need to purchase a new one. If a new code is needed, beware that a new book purchased at the bookstore does not come bundled with the MasteringPhysics access code. The best options are:

1.) Purchase a used book, and purchase the MasteringPhysics access code at www.masteringphysics.com for $44.50.

2.) Buy textbook bundles with MasteringPhysics directly from the publisher at www.mypearsonstore.com. They offer a 10% discount over bookstore pricing, and free FedEx shipping. The upcharge for bundling MasteringPhysics with one book is only a few dollars.

Instructions for logging onto Mastering Physics are located on a pamphlet included in your text and are listed below for your convenience.

Getting started with Mastering Physics : Choose a User ID and password that is different from prevous semesters. You will need a new access code for each course, each semester. Go to www.masteringphysics.com. Find the course textbook image (Knight 2nd edition) and click on it. Next you will need to register by entering:
User ID (you create)
Password (you create)
Course ID:  MPCOHEN52228
Your UMID number

For any technical problems please contact the mastering physics support team by phone: (888) 547-4415 during normal business hours or by email: support@masteringphysics.com

 

Discussion Sections:  The discussion sections have several functions.  One is to provide students a chance to ask questions to clarify issues raised in lecture and the book.  A second is an emphasis on problem solving.  To help make the problem solving component compelling, the sections will generally work on at least some of the current week’s homework assignments---before they are due.  Given this it is strongly in your interest to make an attempt at the homework before the discussion section.  This will enable you to ask the TA to focus in section on those problems which are giving you trouble.  The sections will commonly have a short quiz    

Exams: There will be at least two midterm exams and a final.   You will be permitted to use a one page (both sides) formula sheet prepared by you for the exams.  Much of the benefit of the formula sheet stems from its preparation---the act of deciding which formulae are important enough to include on the sheet will help you to study for the exams.   An electronic calculator is permitted on the exam, but no other electronic devices are. 

Tentative mid term exam schedule:
..........First Midterm Examination: Tuesday,: March 3, 2009.  

..........Second Midterm Examination: Tuesday, April 7,  2009.  

...........  

Final Examination:     The final exam will emphasize the material in the final 3rd of the course.  The current plan is to have a common final for all Phys. 270. The final is set for Saturday, May 16 at 6:30 pm

Grading:  Tentatively the grading for the Phys 270 component of the class will be based on the following weights:  Exams 75%, Homework 20% (10% Mastering Physics 10%), Quizzes 5%..  Note that these are tentative and subject to change.  An attempt will be made to assign grades in as fair a manner as possible and it may be necessary to alter these weights to deal with unexpected circumstances.  Note that homework and quizzes accounts for more than one quarter of the grade.  This means that to do well, you must take these quite seriously.  However, any individual homework assignment or quiz is of rather little weight so that if you do poorly on one it is quite unlikely to affect your grade.   Note, that the grading will NOT follow the silly 90%=A, 80%=B, 70%=C scale familiar from high school.  Rather, the association of grades with percentages will depend in large measure on the difficulty of the exams and will be set a posteriori in order to assign grades fairly.  The PHYS270 component of the grade will be combined with the lab component from PHYS271 (with a weight of 75%  and 25%  respectively) and the final grade will be based on this combined score.  Remember you must separately pass each portion of the course (270 and 271) to pass the combined class.

 

Practice Tests:

First 1/3 of the material (50 min exam)  Practice Exam 1

Second 1/3 of the material (50 min exam) Practice Exam 2

Comprehensive (2 hour exam) Practice Exam 3