Physics 121 Main Handout

Prof. E. F. Redish

Title: Physics 121: Fundamentals of Physics I

The first semester of the two term sequence on introduction to classical physics. Satisfies the physics requirement of most medical and dental schools.

Prerequisites:

Instructors:

Schedule

Recommended Texts:

• Serway & Faughn, College Physics, (6th Edition) Brooks Cole Publishers
• Touger, Introductory Physics: Building Understanding, John Wiley & Sons

Some chapters of my text (a calculus-based text, but more in line with my approach) will be made available online on the our Blackboard page.

• Cummings, Laws, Redish, and Cooney, Understanding Physics, John Wiley & Sons

Website and Email

• Most of the class info is on our website. http://www.physics.umd.edu/courses/Phys121/Redish/

• Contact us by Email! You can send your questions to me at redish@physics.umd.edu. In order to reduce the number of virus-laden e-mails that propagate through the listserve, send messages addressed to the whole class to me and I will forward it to the listserve, which only accepts e-mail from my address. (You are automatically a member of this listserve. You should not need to subscribe. But if you did not get any of the pre-class emails, contact me to add your name to the list.) If you prefer to be anonymous, indicate it in your question to me and I will forward it anonymously to the list.
  
• For your eyes only go to Blackboard! You need your password to access the campus Blackboard account for this class. I use this site for materials that are not for public consumption -- such as solutions to our homework problems or materials that I have a right to use in class but not distribute publically. You can also you this site to have private (among class members only) discussions about the material in the class. Please do not share the materials on this site with others.

Introduction:

Class Participation:

Lectures:

• Lectures will not be traditional! Lecture will include considerable class interaction and will cover material in a way that is decidedly different from the text (indeed, from any text). Lectures may include
  • material that is not in the book
  • demonstrations that may be the basis for an exam question
  • class discussions that may be the basis for an exam question
  If you miss a lecture you are responsible for finding out what was done.

• The PowerPoint "lecture notes" are not the whole story! -- The night before every class, I will post the PP slides to be used in the next day's lecture. Note that these are not the complete content of the class but only a "skeleton outline" of what is being done. You can use them to take lecture notes on, but printing them out is not a substitute for attending lecture.

• You will contribute to lecture! -- In lecture we will be using a Remote Answering Device (clicker). This is like a TV remote control that will let me ask questions and get answers during lecture. The computer records your answer and you will receive one participation point for each click. Although we expect you to give your best answer, you will not be graded on whether the answers you give are correct. Note that these points are given for participation not attendance. You are contributing your answer to the class's discussion of possible answers. If you attend class but forget your clicker you will not get participation points.
  
  The clicker we use is an RF clicker from Turning Point Technologies. This is the campus standard. If you have one from another class, you are likely to able to use it here.
  
  In order to get participation credit from using your click you must register it. Information on how to do this will be given in class and by email within the first few classes. If you join the class late be sure you register your clicker!!

ILDs and Quizzes:

• ILDs will produce structured interactive lectures! -- Some days we will have Interactive Lecture Demonstrations (ILDs) during lecture. During these you may fill out and hand in individual worksheets or work in groups. You get 5 points for participating in each ILD.

• In-lecture quizzes will provide feedback! -- Since the orientation of this class is different from what you might have become accustomed to in high school or introductory college science classes, and to provide you with regular feedback on how well you're making sense of what we're trying to do, we will give weekly (graded) quizzes most Mondays. Quizzes will focus on the important -- and sometimes subtle fundamental issues (often from the previous week's tutorial). Each quiz will be worth 10 points. There will be ~11 of them and the lowest quiz grade will be dropped.

Homework:

• Homework is where it's at in this class! A major part of what I expect you to learn in this class will come as a result of doing homework. Homework will not be a lot of trivial manipulative exercises. There will be fewer problems than are traditional and most will be reasonably challenging.

• Work together! Since the problems will be difficult, it may not be easy to do them entirely on your own. You are encouraged to work together, but each member of the group must fully understand how to solve each problem on their own. ("Oh, I see." is not good enough!) Each person must write up his or her own solution. If two writeups are found to be essentially identical, neither will receive credit. The best way to be sure to not produce cloned solutions even when you work together is to agree on a solution, then each write up the work independently. Do not all copy from a solution you worked out together on the board. Instead, recreate the solution on your own paper and include discussion and explanations of what you have done.
  
• Explanations are essential. On homework (and on most exam problems) you will be expected to include explanations as to what principles you are using and how you know they are relevant. An answer which only includes equations is unlikely to get full credit.

• HW is on the web. Homework will be assigned every Monday and Friday and will be due at the beginning of class one week later. Homework will be posted on our website. Solutions will be posted on our Blackboard site soon after they are due. As a result, late homework will not be accepted. Monday homeworks will be fairly brief and will recap issues raised in tutorial or lecture the previous week. Friday homeworks will be more substantial. (You should expect to spend between 4-6 hours each week on Friday homework.)

• Don't misread the HW grading! Since the TAs are only paid for enough time to spend about 5 minutes on each of your assignments, only one problem per week will be graded in detail on a basis of 0-5 and will provide you feedback. The rest will be scanned for reasonableness and given a grade of 0, 1, or 2. On these "lightly graded" problems, you could get full credit and still have all the problems wrong! It is essential that you read over the solutions carefully in order to understand whether you had the right idea or not.

Tutorials:

Although no participation points are assigned during tutorial sessions, many students find them the most valuable element in the class for learning to do my exam questions and homework problems.

• Discussion sessions are run as group tutorials. -- The discussion sessions will be run as group activities with tutorial worksheets that you will be given when you arrive. The tutorials have two goals:
  1. to help you develop your conceptual understanding of the basic ideas underlying the physics,
  2. to help you learn to think about how you know what you know.

• Get problem help in the Course Center! -- Since we will not be answering questions about HW in the discussion sections, we have set up a Course Center in room Toll 0208. You can come there to check other texts for ideas, to work with other students, and to ask the course center monitor (me or one of the TAs) some questions. Don't expect the monitors to show you how to do the problems, however. The problems are designed so that you learn by thinking about them, not by memorizing them. Monitors are encouraged to ask you questions first, to find out where you are coming from, and then to give you suggestions and hints for what you might try to solve them. Your colleagues are free to tell you anything, but you have to decide if they are right or wrong!

Labs:

• Ya gotta do the labs! -- There will be an introductory lab plus 5 two-week labs during the semester. You must complete all of these labs in order to pass this course. This is a requirement in order to meet professional school criteria.

• These are non-traditional labs! -- Laboratories in this class will involve both exploration and creativity. Instead of being given a long step-by-step procedure, you will be given a question in a sentence or two. You will work in groups of 4 to plan and carry out your own experiment. In a second week you will analyze and model your data mathematically using Excel (a spreadsheet). For more details, see "A hitchhiker's guide to the 121 Lab" for rules and procedures
  

Exams:

• There are 3 exams. -- There will be two midterm exams and a final. All exams will be counted. Each midsemester exam will be given on a Friday (tentatively, on 10/12 and 11/16), and will be returned on the following Monday.

• Missing an exam -- If you miss an exam without a documentable excuse you will get a zero! If you are sick enough to not take the exam you are sick enough to go to the health center. If you have a schedule problem, you must let me know beforehand in order to be able to take the makeup. If you go on another class's field trip or to a sports event without telling me and miss the first exam you can take the makeup but will average in a 0 for the exam! (See below.)
  
• You can improve an exam grade 1: Regrades -- Since we go over midsemester exams in class, you will be able to get a good view of how it was graded. If you think the grader misunderstood what you were saying, or failed to give you proper credit, you can apply to me for a regrade by writing a clear description of why you think you should have more points and turning it in with your exam. (Be sure not to write on your exam itself since this will mean I would have to look up the scanned exams to see what you originally wrote. If you alter a graded exam and request a regrade I will automatically reported it to the honor committee. Don't do it!)

• You can improve an exam grade 2: Makeup exams -- Each midterm exam will be followed by a makeup exam on the Thursday a week after the exam, in the late afternoon. If you miss a midterm, you must take the makeup. If you are unhappy with your grade on an exam, you may take the makeup. If you take both the original and makeup exams, your grade for that exam will be the average of the two grades (whether you do better or worse). Students who carefully consider their errors and understand what they did wrong on the first exam almost always improve. Students who don't do this and just "take another shot" and "study some more" are as likely to go down as to go up.

• The final -- The final exam will be cumulative, but about half the exam will focus on the material done after the second midterm. The final will be about twice as long as a one-hour midsemeter exam, but you will have 4 hours to do it. This is not because it is long, but because I want you to have time to think! Most students find they can finish my final in 2 hours, but the 4-hour period removes the time pressure. (Conflicts will be worked out individually.)

• You will have to think on exams! -- Exam problems will not be standard end-of-chapter problems. You will be expected to think, not replay a previously memorized tape. Questions of the type found on my exams will be included in the homework problems and problems from previous exams will be available on our web site.

Grading:

• Components --

  Hour exams (100 pts each)	200
  Quizzes (scaled to )	100
  Final exam (200 pts)	200
  Homework (scaled to)	200
  Lab (scaled to)	200
  Participation (scaled to)	100
  Total	1000

• How grades are assigned -- I assign a grade level for each category (e.g., how many points you need to get to get an A on the quizzes) and then add them up to get a grade level for what is need for each final grade.

• Curving: Labs and HW yes, exams and quizzes no -- For exams, I do not grade on a curve. I have an absolute expectation. On most exams, 75% will be an A, 65% a B. (These levels may be adjusted somewhat if I feel that an exam is harder or easier than normal.) This means that someone else's doing well on an exam will never negatively affect your grade. If you all do well I will give you all A's.

  Homework and lab grades depend significantly on how the TAs grade. Although I give them instructions, they may not be consistent. After all the HW and lab grades are in I will adjust the grades if a TA's pattern is off by more than a few percent from the average. HW and lab grades will be adjusted so that about the top 25% get an A and 40% more get a B in HW and lab.

• Overall grades -- From past experience with 121, I expect that an A will require about (80 ± 3)%, a B will require about (70 ± 3)% and a C will require about (60 ± 3)% of the total points in the class. The "±" reflects my best guess. This means the odds are 2:1 that the boundary between an A and a B will be somewhere between 77% and 83%. It is not a guarantee.

• The escape clause -- There is an "escape clause" for final grades: If you are below the total needed for a grade but are within 25 points and you are in the next grade up in both homework and the final, I will give you the next grade up. This gives these two activities a slightly more important role in the class than the rest.

Valid excuses:

Honor code:

Prof. E. F. Redish

RETURNS

University of Maryland	Physics Department	Physics 121 Home

Last revision 29. August, 2007.