Physics 135/136/163/164 Introductory Physics Labs
PLU Department of Physics Course Policies
Lab Reports and Evaluation
- Each student must keep a bound lab notebook,
preferably one with at least some gridded pages. A suitable
notebook is available in the Bookstore.
- Each lab report is to be written in pen in the lab
notebook and should contain a brief summary of the purpose of
the lab, as well as clearly marked tables, calculations and
sketches that summarize the data, conclusions and configuration
of the experiment. If data sheets are included with the
laboratory instructions, they should be completed and attached
to the lab notebook. Your notebook should be complete enough
that a knowledgeable reader would be able to replicate your
experiment based upon the written account you provide in your
- Two quizzes will be given (see the lab schedule). You may NOT
use the department-issued laboratory manual during these
quizzes, though you will be permitted to refer to your lab
notebook. Therefore, it's important that your reports be clear
enough for you to extract information from them.
- Your weekly lab exercise will be successfully completed when
your lab report meets the approval of your lab instructor snd
s/he records your lab as having been completed. If your
instructor does not give his/her approval of your report, you
must continue working on the lab until it meets your
instructor's approval. A student who leaves the lab without
obtaining the instructor's approval will not receive credit for
- A student who successfully completes all the labs and takes
both lab quizzes will be assured of at least a "C" grade for the
course. A student with one absence will receive a lower course
grade; two unexcused absences will result in failing the course.
Performance on the laboratory quizzes will provide the primary
basis for assignment of grades higher than C. However, at the
discretion of the instructor, you may be asked to turn in your
lab notebook at the end of the semester. The quality of the
notebook may be used as a grade bump in borderline cases.
- A student may not attend another lab section without the
approval of the instructor of that section. That instructor must
report the student's completion of the lab to the student's
regular lab instructor before the student will receive credit
for the lab.
Guidelines/hints for your lab notebook
When deciding what you should write in your lab book and how you
should write it, the basis for judgment is utility. The first
reason to keep a scientific notebook is to keep track of what
you've done, so you don't have to waste time repeating yourself.
Your record should be complete enough so that you can still
understand what you've done if you were to look at your work six
months later - or six weeks later, during your lab quiz.
- Don't cram everything into a small area on the page. Spread
your writing and drawing out.
- Be complete, but not verbose. Complete sentences not
necessary. Well-labeled sketches are effective.
- Label everything adequately. This includes titling the lab, as
well as calculations, tables of data, drawings, graphs,
In the professional world, your work will probably be challenged;
you will be asked to justify your conclusions or interpretations.
Your lab notebook (or equivalent) will be your best instrument for
defense. Therefore, it should contain enough information to
respond to the skeptic (e.g., your thesis supervisor or your
project manager) who asks:
- What apparatus did you use?
- What data did you take and how did you take it?
- How good/reliable are your data? What is your experimental
precision, and how did you estimate or measure it?
- Why did you take that data? How do (or did) you plan to
transform that data in order to get your final result?
In addition to these topics, lab books often contain the first
preparatory steps toward the interpretation and publication of the
results. Your lab book will also serve as a lab report, so it
should also contain a brief presentation of your results, the
analysis necessary to extract the results from the data, and the
conclusions that you can draw from the experiment. The report will
usually include all or most of the following items:
- Completely labeled graphs and tables of raw and derived data
- A record of how the raw data were used in calculations of
- A record of how the uncertainties in the various results were
- Reasons why you should have confidence in the results. These
reasons usually are in the form of cross-checks: either with
previous experimental results, from independent sources, or