Labs for PHYS 121/122/123 and PHYS 131/132/133

Overview


Your first in-person meeting will occur during Week 3. Full details on how the course will run are below, but in short the format is as follows:

  • There will be 6 in-person lab sessions (Weeks 3-8). Each session will be treated as an independent experiment, and all sessions carry equal weight.
  • Each lab session will be 2 hours and 50 minutes 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 your lab session ends, 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


Spring Quarter: PHYS 123/133

Your first in-person lab meeting will occur during Week 3.

Week Days PHYS 123 Experiment 133 Experiment
1 Mar 18-Mar 22 NO LAB
2 Mar 25-Mar 29 NO LAB
3 Apr 1-Apr 5 Wave Motion and Sound
4 Apr 8-Apr 12 Interference
5 Apr 15-Apr 19 Diffraction Heat and Temperature
6 Apr 22-Apr 26 Geometrical Optics Polarization
7 Apr 29-May 3 Polarization Geometrical Optics
8 May 6-May 10 Radioactivity Diffraction
9 May 13-May 17 NO LAB
Out-of-lab Make-up Assignment Make-Up Lab: Waves
Autumn Quarter: PHYS 121/131

Your first in-person lab meeting will occur during Week 3.

In the meantime, you have an important preparatory assignment (Introduction to Experimental Physics) to complete before the end of Week 2. When you are finished, upload your assignment to Canvas by Friday, October 6 at 5:30 pm CDT to receive credit.

Week Days PHYS 121/131 Experiment
1 Sept 26-Sept 29 NO LAB
2 Oct 2-Oct 6 Introduction to Experimental Physics (No In-Person Meeting)
3 Oct 9-Oct 13 The Period of a Pendulum (Part 1)
4 Oct 16-Oct 20 The Period of a Pendulum (Part 2)
5 Oct 23-Oct 27 Cratering (Part 1)
6 Oct 30-Nov 3 Cratering (Part 2)
7 Nov 6-Nov 10 Simple Harmonic Motion and Mechanical Resonance (Part 1)
8 Nov 13-Nov 17 Simple Harmonic Motion and Mechanical Resonance (Part 2)
- Nov 20-Nov 24 NO LAB / Thanksgiving break
9 Nov 27-Dec 1 NO LAB
Out-of-lab Make-up Assignment Make-up Lab: Paper Drop
Winter Quarter: PHYS 122/132

Your first in-person lab meeting will occur during Week 3.

Week Days PHYS 122 Experiment PHYS 132 Experiment
1 Jan 3 - Jan 5 NO LAB NO LAB
2 Jan 8 - Jan 12 NO LAB NO LAB
3 Jan 15 - Jan 19 Electric Fields I: Field Mapping
(except Monday labs on MLK day)
Electric Fields I: Field Mapping
(except Monday labs on MLK day)
4 Jan 22 - Jan 26 Electric Fields II: Separating Pigments with Electrophoresis Electric Fields II: Acceleration and Deflection of Electrons
5 Jan 29 - Feb 2 Electric Fields III: Characterizing Pigment Motion in Electrophoresis Circuits I: Electrical Measurements
6 Feb 5 - Feb 9 Circuits I: Electrical Measurements Circuits II: Capacitance
7 Feb 12 - Feb 16 Circuits II: Capacitance Magnetic Fields I: $e/m$ of Electrons
8 Feb 19 - Feb 23 Magnetic Field Measurements and Resonance Magnetic Fields II: Field Measurements and Resonance
9 Feb 26 - Mar 2 NO LAB
(except Monday make-up – Electric Fields I: Field Mapping)
NO LAB
(except Monday make-up – Electric Fields I: Field Mapping)
Out-of-lab Make-up Assignment Make-up Lab: Millikan Oil Drop

Lab group assignment


When you registered for the course, you were placed into a 2 hour and 50 minute lab section by the Registrar.

  • The section assigned by the Registrar is the lab section you should attend and no further action is required.
  • If this lab section no longer works with your schedule, you will need to contact Tiffany Kurns (tkurns@uchicago.edu) to switch into a different lab section.
  • All PHYS 121/122/123 labs take place in KPTC 116.
  • PHYS 131/132/133 labs take place in either KPTC 107 or 109 (check the sign on the door to determine which room your section is in).

It is essential that you are in an appropriate lab section by Friday of Week 2. Contact Tiffany Kurns (tkurns@uchicago.edu) with all lab section scheduling requests.

What to do if you are sick or miss lab


If you miss a lab (due to sickness or emergency), please contact both your lab TA and Tiffany Kurns (tkurns@uchicago.edu) as soon as possible. Tiffany will work with you to find a different lab section to attend later in the week (if one is available and you are able). If you are unable to attend an alternate section during the same week as your absence, you will need to complete the online make-up lab. (Speak to your TA for details.)

If you miss more than one lab during the quarter, you must speak with your lecture professor to discuss options.

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.
    • Your lab section was assigned by the Registrar when you scheduled. If that time no longer works for you, you must contact Tiffany Kurns (tkurns@uchicago.edu) before the end of Week 2 to be rescheduled into an appropriate section.
  • 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.