PHYS340 (Experimental Physics) Fall 2015
This course, in which we will perform a number of challenging and not-so-challenging physics experiments, is for
advanced students across the sciences with an interest in physics. The experiments you'll do are more difficult to perform,
analyze, and explain, than those of the Fundamentals... sequence -- and they are
more interesting and relevant to current physics practice (and often a lot of fun to play with!).
this course our goals will be to...
STRIVE to be hands-on in attitude - to create questions, and then to set up the equipment to answer them, taking nothing for
granted about any aspect of the equipment;
MAKE extensive us of equipment manuals and guides to experiments, drawing information and suggestions from them;
LEARN more about the history and context of the labs, by reading background articles, along with textbook material.
STRENGTHEN "lab habits" - writing down what you're doing as it happens, dealing with frustration and triumph, presenting results
to colleagues, and researching background information.
Scott Heinekamp (firstname.lastname@example.org) (http://henry.wells.edu/~scotth/)
Stratton 302 ext 3361
Office Hours Tues 9:30-11:00 & Wed 11:30-12:30 or by appt
ResourcesA modern physics book like Tipler & Llewellyn's Modern Physics, or any other one, should be
in hand (so take one out of the library). Thankfully, many kind people have put helpful documentation on advanced physics
labs on the web, and we will make fairly extensive use of these, too. Finally, to get to
know the particular apparatus you'll use, there's nothing like "reading the manual".
So: obtain a modern physics book.
The key assessment tool for the course is your lab notebook. For this please acquire a 3-ring notebook and a supply of punched paper.
ou may be printing graphs and figures, which can be easily scissored and taped onto blank pages. Some people will be able to maintain a
lab manual in "real time" as an experiment proceeds (and this would be the ideal). Others may want to take rougher notes and then
(perhaps that evening) create a neater and more reflective journal of the labs failures and successes. In any event, your lab manual
should be a complete and unvarnished near-chronology of what you have done. This includes a record not only of actual time and activity
spent setting up and using the equipment, but also notes taken from printed sources; calculations done in support of your own curiosity (or
suggested exercises in a lab handout); and anything else you think I should see in order to form a clear impression of your effort and
understanding. So: obtain a 3-ring binder
General Remarks on the Labs
The labs vary quite a lot in modernity, patience required of the student, and difficulty. Each one is assigned a "week" count, which is a
ough guide both to the time needed to finish it and to the credit you will be awarded upon completion. Of course, many of these labs are
flexible and have optional tasks that might be performed, so these numbers should be regarded as "minimal". You must complete the equivalent
of 12 weeks of labs to pass the course. This can be in a combination that will be worked out between you and me. I will insist that you not
always work with the same partner, in order that we all get to know one another (and learn about collaboration skills!). Sometimes, you will
be working alone and that's good too.
Synopsis of Many of the Labs, From Which You May Choose
Millikan Oil Drop Experiment (2 weeks): until this experiment, only the ratio of the charge of the electron to its mass
(the famous e/m ratio was known. This experiment, which is very tricky to bring to completion, was the first to get the value of
Franck-Hertz Experiment (2 weeks): proves the existence of well-defined electronic states (in mercury, in this case).
The effect is not too hard to see and is quite convincing!
Rutherford Scattering (1 week): an emulation of Rutherford's seminal experiment which proved the existence of a tiny and
very massive nucleus inside every atom. The experiment is easy to do and the analysis requires some amusing trigonometry and geometry.
Electron Beam Physics (Cathode-Ray Tube) (1-2 weeks): a fairly open-ended lab which will teach you about the physics of steering
electron beams, as in an old-fashioned TV or computer monitor.
Cavendish Gravitation (3 weeks): measure the value of the universal gravitational constant G. Requires patience and a
not insignificant amount of data reduction but well worth the effort
Photoelectric Effect (1 week): see the effect and extract a value for Planck's constant
Nuclear Physics (1-4 weeks): all kinds of things are possible here, from simply calibrating a Geiger-Muller tube and understanding
its basic operation, to measuring a half-life, to studies of absorption of radioactive particles by matter, to use of a cloud chamber
to actually see tracks
Microwave Diffraction (2 weeks): chemists and physicists alike will appreciate this lab, which illustrates the wave-like nature of
electromagnetic radiation using wavelengths are not hundreds of nanometers (like visible light) but instead a few centimeters
Charge-to-Mass Ratio of the Electron (1-2 weeks): new equipment for Wells and illustrative of a number of important physics concepts.
See the Millikan oil-drop experiment. By accelerating an electron to a known speed and then bending its path into a circle, one can measure e/m.
Two Very Sophisticated Setups Which Every Student Is Required to Try Out (at Least in an Introductory Fashion
Diode Laser Spectroscopy (2-4 weeks): New equipment for Wells, (crafted by TeachSpin, a great little company in Buffalo): provides a way to do incredibly precise measurements of atomic transitions.
This is a very elaborate apparatus, and involves a lot of careful optics work, along with a lot of fascinating theory.
Fourier Methods (2-4 weeks): Another incredibly versatile apparatus (also from TeachSpin), this is an extremely well-designed set of experiments for exploring the wonderful world
of signal processing and the Fourier approach to it.
Course Requirements and Grading
Regular submission of lab notebook (30%) - to be evaluated based on
thoroughness, coherence and its value as a potential historical
artifact. Every lab you do needs to be contained in this notebook.
Effort and quality of independent work in the lab (30%) - regular and enthusiastic
investigation of the equipment and physical phenomena.
Formal write-up + 2 Oral presentations (25%) - Formal writeup is to be 8-10 pp, including figures and
equations; your oral presentations will be 10-15 minutes, on labs you did that perhaps others did not do, or introductory tutorials based on library research that you present in order to arouse curiosity among your colleagues (and, it goes without saying, yourself).
Final report (15%) 10-12 pp, on an experiment you did, or one that is famous, or both. Writeup should
convey the importance to physics (and beyond) of the experiment you've selected; it should contain
sufficient physics explanation (with equations/figures) for an intelligent adult to understand
what's going on; it should discuss the technology of the experiment itself. Make sure
each part of the writeup directly relates to the
other parts: make it well-integrated as a document. Standard citation style (APA preferred) should be used, with sources to include AJP, Scientific American, and Physics Today articles, along with a judicious selection of web sources.