Labs for PHYS 131/132/133 (Summer Session)

Overview


Full details on how the course will run are below, but in short the format is as follows:

  • There will be 4 in-person lab sessions per course. Each session will be treated as an independent experiment, and all sessions carry equal weight.
  • Each lab session will be 3 hours and students are expected to attend for the full time.
  • Students will work in groups of 3 and will collaborate on a digital group lab notebook. This notebook will be due at the end of each session. Students are graded individually on participation during the session and as a group on the completeness of the lab notebook.
  • After the conclusion of each lab, each student will submit an individual short Post-Lab Assignment in which you may summarize work, answer specific questions, or draw conclusions about the experiment you just finished. This is due 24 hours after the completion of your lab session, and the TA will give the report a numerical score based on quality.

Our goal with this lab sequence is for you to gain practice doing experimental physics. While you will see many of the phenomena discussed in lecture show up in these labs, the point is not just to repeat that content but to use that content to explore and learn the scientific process. Put succinctly, the goal is to understand how we know, not what we know.

Lab schedule (Summer Session)


You will be assigned to work on your lab in either KPTC 107 or KPTC 109. All labs take place from 2:30-5:30 pm on the days listed below.

If you miss a lab (due to sickness or other excused emergency), please contact both your lab TA and the course instructor as soon as possible. You will need to complete the online make-up lab for that quarter in order to get credit for the missed lab. (Speak to your TA for details.)

PHYS 131 Labs

PHYS 132 Labs

Week Monday Lab Thursday Lab
4 July 4
NO LAB
5 July 8
NO LAB
July 11
Field Mapping
6 July 15
Acceleration and Deflection of Electrons
July 18
Circuits I: Electrical Measurements
7 July 22
$e/m$ of Electrons
- Make-up Lab: Millikan Oil Drop

PHYS 133 Labs

Week Monday Lab Thursday Lab
7 July 25
NO LAB
8 July 29
Wave Motion and Sound
Aug 1
Interference
9 Aug 5
Diffraction
Aug 8
Geometrical Optics
10 Aug 12
NO LAB
- Make-Up Lab: Waves

Lab format


Goals

For the introductory physics laboratories here at the University of Chicago, we have adopted a set of learning objectives. By the end of this lab sequence, you should be able to do the following:

  • collect data and revise an experimental procedure iteratively and reflectively;
  • evaluate the process and outcomes of an experiment quantitatively and qualitatively;
  • extend the scope of an investigation whether or not results come out as expected;
  • communicate the process and outcomes of an experiment; and
  • conduct an experiment collaboratively and ethically.

Put succinctly, the goal is to understand how we know, not what we know.*

* These goals were first outlined by the Physics Education Research Lab at Cornell University for labs at all levels, but especially for introductory labs. You can read more about the philosophy behind these learning goals  here.)

Each lab you work on this year will relate back to one or more of these course objectives and will help you develop and apply the tools of experimental physics. The aim is to teach critical thinking through experimentation, and for you to see how the concepts of lecture are applied (and limited by) specific physical situations.

Lab "projects"

  • Each session lasts 2 hours and 50 minutes, and you are expected to arrive on-time and stay for the entire period.
  • In lab, you will work in groups of three students.
    • Your group will record observations, data, photos, and calculations in an electronic lab notebook. This notebook will be useful in discussions with your TA and for drawing conclusions at the end of project, but it is a working document that is not expected to be perfect, polished or even correct.
    • You will submit a copy of this notebook via Canvas before the end of the lab period. Your TA will grade the notebook for completeness only; you will not be graded on data, conclusions, notes, or anything else related to “correctness”.
  • Once the experiment is over, you will turn in a short individual post-lab assignment that is specific to that experiment. The assignment may ask you to provide a summary of the experiment (only the most important information), to answer specific questions about the experiment (or related work), or to draw conclusions about your work. 
    • This assignment will be graded on quality and correctness. (Not on the correctness of your results/answers, but on the correctness of your reasoning and conclusions.)
    • Each lab will outline what you should include, and you should talk to your TA if you have questions (especially in the first few labs as you are just getting started). 
  • Points will be assigned for different parts of the project based on participation, your group notebook, and the quality of your submitted post-lab assignment.

Grading

The rubric for the every project this quarter is identical and is shown below. Your work in-lab (e.g. your completed lab notebook and participation in group meetings) is worth 4 points and your out-of-lab report (e.g. answers to questions and/or summary and conclusions) is worth 4 points.

Complete (2 points) Needs improvement (1 point) Not acceptable (0 points)
Lab Notebook (Group) Submits a lab notebook at the end of the meeting that shows reasonably complete notes and data for all the tasks assigned for that session. Submits a partial lab notebook with important details missing, or submits a notebook that lacks care and is rushed. Does not submit a lab notebook, submits a lab notebook that is missing significant sections, or submits a lab notebook after the meeting has ended.
Participation (Individual) Comes to the lab on-time and prepared, and stays until the group is completely finished.

Is an active participant in the experiment, but also shares responsibilities and makes sure that all partners get a chance to contribute as well.

Answers TA and group questions, and participates in a meaningful way during discussions.
Either arrives late or leaves early, or otherwise comes to lab unprepared.

Is either reluctant to participate in the experiment or overly dominant in a way that makes it difficult for partners to participate.

Is unable to answer TA and group questions, or does not participate in discussions.
Misses most or all the session, or is “not present” (i.e. doing something else) during the period.

Is disruptive or disrespectful to the group or to partners, or has an attitude that makes it difficult for the class or group to make progress.
Complete (4 points) Needs improvement (2 points) Not acceptable (0 points)
Report (Individual) Answers questions thoughtfully and completely.

Clearly presents important data in tables and graphs, and appropriately labels and describes these data (including units and use of appropriate significant figures).

Includes correct units and appropriate number of significant figures on all calculated values.

Makes conclusions that are complete, and clearly supported by the data. Compares data to models or predictions (where appropriate) and include uncertainties in that discussion (if applicable).
Attempts questions, but does not support answers fully or correctly.

Does not present data appropriately, does not include units on values, or does not keep appropriate significant figures.

Is unclear or makes major mistakes in reporting or summarizing work.

Makes conclusions which are mostly correct, but which miss minor points.

Does not use data as effectively as possible to support conclusions.
Does not answer meaningfully.

Presents no data or plots (where appropriate), or presents data in a confusing manner.

Provides incorrect units or makes fundamental flaws in calculations that render the answer meaningless.

Makes conclusions that are directly contradicted by the data, overstates conclusions beyond what the data support, or is unclear in how conclusions are derived.

Uses unsupported speculation to explain discrepancies in their data rather than well-reasoned arguments.

Guidance for writing your summary and conclusions

After your experiment has finished, you will need to write up your summary and your conclusions. This should be a separate document, and it should be done individually (though you may talk your group members or ask questions). Include any data tables, plots, etc. from the your lab notebook as necessary in order to show how your data support your conclusions.

The summary is just a retelling of the facts. What were the important things you did? How did you make measurements? What changed as you worked through the project? What are the take-away results?

The conclusion is your interpretation and discussion of your data. What do your data tell you? How do you data match the model (or models) you were comparing against, or to your expectations in general? (Sometimes this means using the $t^{\prime}$ test, but other times it means making qualitative comparisons.) Were you able to estimate uncertainties well, or do you see room to make changes or improvements in the technique? Do your results lead to new questions? Can you think of other ways to extend or improve the experiment?

Each of these above sections does not need to be long; one or two paragraphs for the summary and another one or two paragraphs of conclusion should be sufficient. What is important, however, is that your writing should be complete and meaningful. Address both the qualitative and quantitative aspects of the experiment, and make sure you cover all the “take-away” topics in enough depth.

Don't include throw-away statements like “Looks good” or “Agrees pretty well.” Instead, try to be precise, state your facts clearly and honestly, and don't overreach or stretch your conclusions beyond what the data tell you.