It is easy to lose sight of the fact that all science is based on experiment, either to test the predictions of theories or to present data the theories cannot explain in order to spur better theories. Over a period of centuries, millions of researchers have taken painstaking measurements, analyzed the data, and fit the data in theoretical models to give it clarity, meaning, and predictive power. We have no knowledge a priori that there should only be three forces (the search is still on for evidence of additional forces and work is in progress to unify the existing forces). There is no way of knowing that the conservation laws should hold everywhere on this planet or across the universe. This knowledge is obtained by careful observation and a self-consistent understanding of these observations.

If you find science difficult, you are not alone. The concepts themselves are often not easy to grasp. Research has shown that we each must construct our own models of understanding. Simply listening to lectures and rote memorization are not good ways to learn. We must be able to assimilate the concepts and apply them to predict further phenomena. Research has also shown that learning improves when a student thinks about a concept or problem by him/herself first and then discusses it with a small group of peers. That is the philosophy we will follow in this workshop. The abilities to work within a group of peers and to communicate ideas, both orally and in writing, are important skills to have. These are fundamental goals of this workshop.

We expect that many of you will not have extensive experience in doing experimental science. We expect to help you learn how to approach measurement and experiment with more confidence. Often the difficulty is to determine just what needs to be measured. Figuring out a way to isolate a particular phenomenon to measure or to test complicates things, because usually changing one parameter may affect several others. Identifying and then minimizing or eliminating systematic and random errors requires great care and stamina. Yes, science can even be tedious. However, the reward is great: You come away with a rich understanding of the phenomena you are studying and therefore a better understanding of the world around you. You develop important skills as you practice the scientific method. You build your confidence in your ability to test and understand the "rules" of nature. Your understanding, the skills you develop, and the confidence you build allow you to identify and tackle problems you have not seen before or for which you have not been specifically trained.

The purpose of this workshop is

1. to teach you some important physical phenomena and concepts,
2. to teach you to think for yourself and to work in groups of peers,
3. to teach you better oral and written communication skills,
4. to introduce you to proper laboratory procedures and teach you some basic laboratory techniques, and
5. to give you confidence in your ability to take measurements and adequately analyze and interpret data.

Physics 142W is part of Physics 142E, but it is a separate one hour credit course. You must be registered in both a 142E lecture and a 142W workshop. Each workshop section will have up to 24 students (and no more).

Every student must purchase the manual for Physics 142W at the Newcomb Hall bookstore. This manual contains the workshop activities, CD-ROMs for some laboratory experiments, and a booklet number that must be given to Larry Suddarth in the lab tol allow you to sign in for WebAssign,, an Internet web server that will be used to grade your homework problems. You cannot share this control number with another student, so you must purchase your own Physics 142W manual.

Registration in Physics 142W will be blocked on the semester’s first day of classes. The workshops start on Monday during the semester’s first full week of classes (January 22, 2001). In that first week, you must attend the section of your choice on time. If you are registered for that section, your place in that section is secure. If you do not attend or are late to your registered section, your name will be dropped from that section’s enrollment. Those who wish to add to that section will then be added if space is available. Since only 24 students may be in a section, if more students want to add than is space available, names will be drawn at random and added to the enrollment until the 24 spaces are filled. The remaining students must find other sections to attend. Let us re-emphasize this point: If you are registered for a section and wish to secure your place in that section, you must attend that section on time during the first full week of classes. Note, however, that there are two sections being held simultaneously so that each time slot has space available for 48 students in the two sections. In the extraordinary event that you cannot attend any sections during that first full week of classes, say due to illness or a death in the family, please contact Larry Suddarth (room 214 – physics building, 243-6843, lts7x@Virginia.edu).

It is your responsibility to be registered for a workshop. If you are unable to find a workshop open that meets your schedule, you may try to find someone to switch with you. The best way to do this is to go to a suitable section the first week to see if space becomes available or to see if someone will switch with you.

Your work in Physics 142W will consist of two parts:

1. a pre-lab activity that you must complete before coming to the workshop.
2. performing the workshop itself and keeping a journal of your and your group's work that will be turned in at the end of the workshop. You will not be writing a lab report for this workshop. Sometimes you will turn in an individual journal and sometimes a group journal.

Each workshop is two hours (technically one hour and 50 minutes) long. You are expected to have vacated the room within one hour and 55 minutes to allow the next section to begin on time. The workshops meet during each full week of classes and are overseen by both a faculty member and a graduate instructor (teaching assistant commonly called a TA, for short). The graduate instructor’s responsibilities are to ensure the safety of the students; protect the equipment; provide good teaching pedagogy to help you learn as much as possible, provide additional instructions and information concerning the workshop, grade your pre-lab activities, journals, and in-lab quizzes and, together with the faculty member, assign your PHYS 142W grade.

The first part of the first meeting of the semester will be organizational and preparatory. You will be added or dropped from the section (as discussed above), meet your faculty member and graduate instructor, exchange information with your instructors, be informed of any changes to class policies, etc. In addition, you will perform the first workshop activity. We generally try to have activities on material that you have done the previous week in lecture. Some weeks we are not as successful in doing this as for other weeks.

For each workshop, you must do the pre-workshop activity which can be found on the Physics 142W web page (http://www.phys.virginia.edu/classes/142w.stt.spring01/). It is important for you to look at this page often, because any changes to this manual will be given there. For some weeks, the pre-workshop activity will be something you will print out, complete, and turn in at the beginning of your workshop. On other weeks, the activity will be given on WebAssign, and you will need to complete the answers online by a given deadline. IT IS YOUR RESPONSIBILITY TO LOOK AT THE WEBSITE OFTEN ENOUGH TO BE AWARE OF THE WEEK'S ASSIGNMENT, PRE-LAB ACTIVITY, AND CHANGES IN THE WEEKLY WORKSHOP. We are not having you submit a lab report as has been done in the past, but in exchange, we are requiring you to spend time preparing for the workshop each week. We expect that since you are better prepared, the workshop will be a better learning experience. We would like you to bring a graphing calculator capable of entering data and doing at least linear best fits to data.

In order to complete the pre-lab activity each week, you should do the following:

1. Read over the workshop material in this manual (including the relevant appendix and outside reading assignments, where appropriate) for the week’s activity completely to get an overview.
2. Connect to the Physics 142W web page (http://www.phys.virginia.edu/classes/142w.stt.spring01/) to learn about any changes, suggestions, or additional material given for this week's activity.
3. Read the instructions again, but this time more carefully; highlight the important features of the workshop. Try to work through any derivations you do not understand. In other words, be an active reader and study the manual.
4. Watch the video that is given on your CD-ROM included with this manual. There is a video for all but one of the labs.
5. Complete the pre-workshop activity as directed on the web page.
6. Bring linear graph paper to the workshop. It should have at least five (5) and preferably ten (10) rulings per centimeter.
7. Bring a graphing calculator to the workshop. If you do not own one, perhaps you can share with someone.

This workshop manual will sometimes indicate special materials such as logarithmic graph paper, etc. that may be needed for an experiment. You should bring these materials with you. In general, preparing well beforehand will save you time and trouble in the workshop, where you may often find yourself under time pressure.

Before attending your workshop section during the first full week of classes, look over the workshop manual and become familiar with the appendices to which you should refer as needed throughout the semester. Particularly important are Appendix B: Graphical Analysis, Appendix D: The Accuracy of Measurements and Significant Figures, and Appendix E: Vectors. Refer to Appendix D and apply it appropriately in your lab journals throughout the semester.

Since the workshop periods are two hours long, you will need to be efficient in the use of your time. Normally you will work in groups of three or four. You will be assigned to a different group each week. We encourage a free exchange of ideas between group members (and also generally in the laboratory), and we expect you to share both in taking data and in keeping the lab journal. You and your group members will not necessarily receive a common grade for the workshop journal because some of it will be individual work and some of it will be done jointly.

You will note that some weeks, you will perform a standard laboratory experiment during the workshop; some weeks, you will work through a prepared tutorial that will help you learn and apply concepts; and yet other weeks, you will do a combination of the two. We will try to make it clear to you each week what you will be doing and how your journal should be prepared.

The material in the journal will be somewhat different depending on whether you are doing a lab experiment, a tutorial exercise, or a worksheet.

An essential part of all scientific experiments is a carefully kept record of everything that is done in the laboratory. Your journal might be a group effort in this case, and it should be done in pen (NOT pencil), preferably in blue or black ink (NOT red) and should include the following:

• The date and group members’ names.
• Brief descriptions of what you do for each part of the experiment along with sketches of the apparatus.
• Tables of the data as they are taken.
• Notes on difficulties in taking data and how you circumvented these difficulties.
• Plots of the data, properly labeled and with correct units.
• Results of data fits with graphing calculators, including equations and parameter values.
• Data analysis and conclusions (include proper significant figures, random error calculations and systematic error estimates, etc. Do things make sense? How do the results compare with theory?).
• Observations of unexpected occurrences and effects.
• Answers to all the questions posed in the manual.
• A pledge that the work is yours. No pledge, no credit.

Write down all these things as you go along. All mistakes must be clearly crossed out; they should not be erased or whited out. Both the original and the new recordings must be visible.

We may not require you to turn in the answers to the tutorial sheets. The primary point of the tutorial is for you to learn. We are not as interested in the mistakes you make during the learning process as we are in the end result. Research has shown that students learn significantly better in this cooperative atmosphere. The workshop instructors will be coming by and visiting you often during the tutorials. You will be asked questions to check your understanding. Your questions to them will normally not be directly answered, but you will be given a response to help you understand and figure out the result. We will check to make sure that you are writing down your individual response to a question and to the group response when directed to do so. If we find that students are not doing this, we may require these responses to be handed in. You would never be graded down if your initial ideas were incorrect. We are primarily interested in the final conclusions after you have performed an activity or thought through an activity. We want to encourage free thought.

We may also decide to have you write out individually a journal response to tell us what you have learned during the workshop. More details will be given about this later. Check the web page.

For those weeks in which we have you complete worksheets, you will be expected to hand those in individually with your journal. Note that often you complete these worksheets together in your group, but we want your sheet to be completed by you!

The completeness of the workshop journal is of the greatest importance. Later in your professional career, whether you will be a researcher writing a paper about an experiment completed a year ago, a physician who is studying an old case history, or an engineer going over some earlier test protocol, you will always wish that the notes that you had made at the time were more complete. All the details that were then too obvious to be written down will now be forgotten, the abbreviations that were self-evident will now be mysterious, etc. Sometimes, the experimental apparatus must be torn down before you can complete a full analysis of your data. It is vital that your results be completed while you still have access to the experiment. Preliminary plots and data analysis in lab give you an opportunity to catch and fix mistakes during the lab.

An example of what an adequate laboratory journal might look like is shown in Fig. 1 (this figure is not shown on the webpage). Notice several things about this example, which is for a laboratory experiment. The pertinent facts and procedures are recorded briefly but clearly. The journal contains a brief sketch of the apparatus, a table of the data as they were taken (with the proper units), a simple graph (with properly labeled axes), and an analysis that shows that the experiment was successful. Some questions to ask yourself are: Did you follow a reasonable strategy in this lab? Did you write down all relevant information? Can the reader tell from the journal what you did and why? Could you, or anyone, make sense of your journal six months from now? Mention extra measurements that you performed. You should attach your individual work together with that of your group journal in the case of you having group results.

Each week's activity will be graded as follows:

• The pre-lab activity is worth 5 points.

• The journal is worth up to 10 points based on the performance in the laboratory as evidenced by the journal section of your write-up (see the discussion above).

Your final workshop grade will be determined by taking the average of all your workshop grades. No workshops will be dropped. Grades will be assigned on a curve based on your graduate instructor’s students only. Each graduate instructor typically teaches three sections.

Absences and tardiness will be accepted only for legitimate excuses, i.e. illness, a death in your family, a university sponsored trip, etc. If possible, contact your graduate instructor before the time of the lab (e.g. send an email). Without a bona fide reason, all absentees receive a grade of zero for that workshop. If you miss a laboratory session because of a legitimate excuse, your lab instructor may allow you to make up the workshop on Thursday at 4 pm. In order to be excused, you must submit a written excuse petition signed by you. This should be done no later than the next scheduled lab period. For approved absences, it may be possible to make up a missing workshop, but it must be done no later than the Thursday of the following week. See your graduate instructor or faculty member for further information.

Late arrival for any lab session is very disruptive and will be penalized. After a 10-minute grace period, the lab instructor will deduct two points from your grade during the first 15 minutes of tardiness and an additional two points for each successive 15 minute period (or part thereof).