Introductory undergraduate labs are a recurring challenge at nearly every university. Is the purpose to teach students something about how experimental science works (formulating hypotheses, defining measurement needs, setting up equipment, acquiring and analyzing data)? Is the purpose to emphasize and reinforce specific scientific points from the curriculum? How structured should they be? Where are there opportunities for interdisciplinary labs rather than traditional physics/chemistry/biology/earth sciences stovepipes?
(I tried launching a survey about undergrad physics lab instruction five years ago. I got zero responses. Hopefully this will be a little more successful.)
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ReplyDeleteAnon@4:35 - that was concerning. Please take care. https://988lifeline.org/
ReplyDeleteI don’t know if I’m the right person to comment given that I’ve only ever done research in theory and I was always out of my element in my undergraduate physics labs. But I have often regretted that I didn’t get a deeper understanding of experimental physics from my courses. I can’t say I have examples of good courses but I do think I can say something about things that, in retrospect, I think could have been done differently at my institution.
ReplyDeleteMy institution had a “hands-off” philosophy for physics labs. They believed in giving students minimal instructions, leaving them to their own devices to figure out what had to be done. The introductory course lab manual in fact included the following passage:
“ A great chef uses a recipe as a source of ideas, as a
suggestion about how to accomplish a goal; she or he
doesn’t necessarily follow the recipe meticulously, the
way a lesser cook might. It would be possible for us to
spell out in excruciating detail each step you should fol-
low in conducting the experiments of this course, but
we choose not to. We are uninterested in educating
lesser cooks who are bound merely to follow the recipes
developed by others. Such an approach gives an impov-
erished view of experimental science. Rather, we want
you to understand how to conduct original research,
which involves experimental design in addition to care-
ful observations and analysis. We won’t be answering
for you questions such as
• “How many data points do I need?”
• “Do I need to measure both doublet lines, or is
one enough?”
• “Should I measure the resistance of the induc-
tor?”
• “Can you set up this circuit for me?”
even though this may frustrate you at times. Learn-
ing how to answer such questions is an important part
of understanding what it means to conduct an original
experiment.”
Looking back, while I understand in retrospect what they were trying to do, I have come to believe that this is not the right approach for an INTRODUCTORY lab course. In practice, what inevitably ended up happening was that the students who did best in such labs and gained the most out of it were those who had privileged backgrounds that afforded them lots of previous exposure to “hands on tinkering”. These students had the advantage that they didn’t have to invest excessive intellectual bandwidth “learning the ropes” of how to actually use the equipment. Thus, these students were able to focus on those aspects that are truly the essence of experimental physics: designing the experiment, analyzing the data, performing the right follow ups. But for students without such previous experiences to fall back on (like myself), it was like trying to do heavy duty E/M or quantum mechanics problem sets without having first learnt calculus or linear algebra.
I suspect that I’m probably going to get a lot of pushback in this, but I’ve thought that for introductory lab courses, it might be worth having students first learn how to do experiments in a “virtual” setting. That allows for learning the basics of experimental design, documentation, analysis, comparison with theory, reporting, in a way that reduces the required prerequisite familiarity with “hands on” tinkering. Then, after the students have mastered virtual experiments, you gradually transition them to the real world so that they learn in steps how to handle the challenges and inevitable equipment failures that emerge, but in a way such that they have a better sense of how those problems influence the bigger picture and end goals of the experiments.
Just a few thoughts.
I'm not as familiar with our intro labs here at Case Western Reserve and we've recently had an increase in undergrad enrollment (50% increase over the past ~4 years) that has made getting students to register and fit into the labs our priority over changing our curriculum!
ReplyDeleteBut something I find interesting with physics vs. some other STEM fields is how the number of labs and the topics of labs for the entire BA or BS degree vary from university to university. This is in contrast to my training in chemistry where the labs are pretty set for all programs (e.g., gen chem I and II, ochem I and II, analytical, thermo, quantum, inorganic). CWRU's BS degree I think ends up with at least 6 semesters of labs and then a year-long senior project while our PhD program requires a graduate lab course. Our intro labs are pretty structured, worksheet format compared to our upper level labs are very open ended. Our alumni end up coming back with some reflection on appreciating the amount of lab work they had (with all the pain and learning that comes with it!). But it seems like this may be on the heavier side of lab courses for a physics program.
I think your points on what the purpose of the labs are important too - physics uniquely has pretty much all the engineers, pre-meds, and science majors go through the labs so probably the most diverse audience of students in a lab course.
Lydia Kisley
Much the same questions and issues pertain at the secondary level, too. College Board insists that AP Physics be lab-based (and I agree!) but also loads the courses with tons and tons of content.
ReplyDeleteProf. Natasha Holmes revamped our intro physics labs at Cornell. Her research is in exactly the questions you are asking, and her publications on this topic can be found in her earlier work in her list of publications here: https://physics.cornell.edu/natasha-holmes
ReplyDeleteThanks, everyone - I'm already aware of the great work done by Natasha Holmes at Cornell on this topic, as well as Heather Lewandowski at Colorado. Does anyone have any examples of undergrad lab facilities that are particularly excellent? I feel like the right teaching spaces and capabilities can make it easier to enact the pedagogical changes suggested by those recent lab education research outcomes. Can anyone recommend specific buildings/facilities/spaces that have been built in, say, the last 15 years?
ReplyDeleteDoug, I'm going to connect you by email with the associate director of MIT's Junior Lab program (https://web.mit.edu/8.13/www/index.shtml). Setting up the right facilities and -- importantly -- maintaining them is a huge part of how our department teaches this topic, and I think our associate director would be able to tell you about them. I personally think they are pretty excellent, but I'm sure the in-house experts can tell you what works and what doesn't, and why.
ReplyDeleteWhoops, just noticed you're asking about _intro_ labs. My dumb; our intro labs are not so great. Happy to connect you if interested, but I now realize I may have enthused about the wrong topic...
Deletemaybe something to send/contact the AAPT about?
ReplyDelete