E&M General Announcements

Read the announcements for each individual experiment before beginning that experiment.

1. Dr. Diana. Driscoll is in charge of the laboratories. Office: Rockefeller 222A, Phone: x-8844; e-mail: diana dot driscoll at case dot edu

Dr. Minhua Zhu is a lab supervisor. Office: Rockefeller 201E, Phone: x-4030; email: minhua.zhu@case.edu

2. The manual for the course has been revised. You must purchase a new manual, which covers the Physics E&M lab, from the bookstore. You can copy the Microsoft Word^® versions of every part of the manual from the lab server (Wertsrv) P: drive in the “E&M Manual” directory. Log on to Wertlabs - Wertsrv with user name: RemoteLab and password: uglabs. (You may NOT print out your own copies of the manual with the Undergraduate Lab printers!) There is also a pdf version of the manual available on the web but, because of file conversion problems, there may be errors and missing pages in these documents. The printed version is the official document. (Note: The lab manual online is outdated! It will be updated as soon as we get a chance to work on it…)

3. You must bring a lab notebook to lab. Only bound notebooks that generate a duplicate copy of your notes are allowed. You must hand this copy in to your TA at the end of your lab period. You may re-use your notebook from last semester, if you have one. Also bring a calculator and a pen to class. You need a pen that will make legible duplicates of your notebook pages; soft tip pens will not work reliably.

4. There will be at most only very short lectures at the beginning of the lab. Experiments will occasionally be scheduled before the relevant theory is covered in the course lecture. Therefore you must read the pertinent section(s) of the manual and read the pertinent announcements on the lab web before coming to lab. This is particularly important since the amount of material covered in each E&M lab is much greater than in the Mechanics labs. You may NOT be able to finish the labs if you must read the manual for the first time when you come to lab.

Before coming to your first lab, read Lab #1, DC Circuits. You should also scan through the preface, introduction, lab sermon, and the appendices (particularly Appendices #1—Notebooks and #2—Reports) and note changes in policies and procedures from last semester.

5. Updates and corrections to the labs are posted on the lab web page. Read this information before you begin your experiments. The lab web site is http://physicslabs.phys.cwru.edu/EM/ementry.html.

6. Check your schedule to be certain you show up at the right time for your lab. See the table of classes below. ODD refers to the first week of classes and every other week after that, and EVEN refers to the second week of classes and every week after that.

7. Rooms 402 & 403 in Rockefeller are the E&M labs. Come to Roc 403 at the beginning of the first lab period for some brief announcements.

8. If you wish to change lab sections, consult the Registrar’s searchable schedule of classes to determine which sections still have space. The list of sections is reproduced on the next page.

After classes start, you may not change lab sections without a permit. These permits must be obtained from Dr. Driscoll. This can be handled by email. Generally you will NOT be given an override for a full section if you can make any other lab time, include nights and mornings.

If there is some doubt about your getting into your preferred section, come to the earliest lab (early in the cycle for labs) that you might attend, whether you are registered for it or not. Waiting and coming to a later lab to which you might not be admitted could mean that you get into no lab at all, if that later lab is full. If you come to an earlier lab for which you are not registered and there is room, you can obtain a permit in class that will let you stay in that lab permanently, turning in the form later that day or the next to formalize the arrangements. If you want to switch to a lab later in the cycle, you might have to do the first lab at your scheduled time and come to the later lab also to see how many of the registered students actually show up.

9. Students agree that by taking this course, all required lab reports or other assignments submitted for credit may be submitted to TurnItIn.com or similar third parties to review and evaluate for originality and intellectual integrity and that if the results of such a review support an allegation of academic dishonesty, the course work in question as well as any supporting materials may be submitted to the Office of the Dean of Undergraduate Studies for investigation and further action. A description of the services, terms and conditions of use, and privacy policy of TurnItIn.com is available on its web site: http://www.TurnItIn.com. Understand that all work submitted to TurnItIn.com will be added to its database of papers.

Lab Section	CRN	Day	Time	Even/Odd	Enrollment/ Limit
Lab #1	2952	Wednesday	3:00-6:00 PM	odd weeks	28/32
Lab #2	2300	Wednesday	6:30-9:30 PM	odd weeks	16/16
Lab #3	2302	Thursday	8:30-11:30 AM	odd weeks	15/16
Lab #4	2304	Thursday	1:15-4:15 PM	odd weeks	26/32
Lab #5	2306	Wednesday	3:00-6:00 PM	even weeks	27/32
Lab #6	2308	Wednesday	6:30-9:30 PM	even weeks	15/32
Lab #7	2310	Thursday	8:30-11:30 AM	even weeks	13/16
Lab #8	2312	Thursday	1:15-4:15 PM	even weeks	26/32

Note: Italics means P113B students.

It is better NOT to fill in the worksheet as you do the lab. The worksheet is not turned in for another week and you can complete it more carefully if you delay filling it in until later. All of your data (and analysis) needs to be entered into your notebook anyway. Although the carbon copy of your notebook must be handed in before you leave the lab, you will still have the original copy in your hands and can use it to complete the worksheet.

The second sentence of the last paragraph states that the worksheet is due one week after doing the lab!

Figure 5 in your manual, the circuit layout, only shows the bottom two-thirds of the Pasco board. Orient the board with the 4 spring 'pads' along the bottom (and below the batteries) when you construct this circuit, as shown below.

Use as many significant figures as possible on your DMM - this will usually be 3 or 4. If you have only 1 or 2 significant figures, try to use a more sensitive scale if one is available.

When using the DMMs, remember to plug the probes into the proper jacks - you always use the common jack for one probe, by convention this is usually the black one, but different jacks must be used for the second probe for current measurements as opposed to voltage or resistance measurements.

1. Usually, this is due to loose connections. Wiggle each of your connections while watching your DMMs to see if you can spot the troublemaker.

3. The various switches and pots on the board can have poor internal connections. Press the buttons a few times and rotate the pot (if it's connected to your circuit) to see if they are causing the trouble. Sometimes the pots will be noisier at the very end of their limits of travel. Back it off a quarter of a turn and, if your circuit behaves better, don't use the pot at its limits.

4. Because they are bent so frequently, we have seen wires that break INSIDE their insulation where you can't see the break. In this case, wiggling the wires will usually cause the DMM readings to jump.

5. A previous user may have fried your DMM. Try a simple reading with the meter to see if it works or try temporarily substituting another DMM.

Note that you are NOT supposed to measure the sum of the series (or parallel) resistors with the ohms function of your DMM. You are to determine these sums from your measurements of V and I. This is the experimental sum that you must enter in the fourth column of the tables you must create.