PHYSICS 59: ADVANCED LABORATORY I
Quantum Physics, Nuclear Science, and Nobel Prize Experiments
Offered each SPRING semester.
Instructor:
Dr. Athan Petridis
Harvey Ingham Hall, Room 31C
271-3723
athan.petridis@drake.edu
Office hours: MR 2:00 pm - 4:00 pm
Meeting Time: Friday 2:00 pm to 2:30 pm.
Place: Harvey Ingham Hall, Room 19.
Lab Time: When students can work. At least 2 hours per week in the lab.
1. Nuclear Instruments
A. G/M Tube-Plateau and Background.
B. Scintillation Tube-Plateau; Background.
C. Resolving Time (optional).
2. Nuclear Interactions
A. Beta Particle Absorption in Aluminum.
B. Gamma Absorption in Lead.
C. Half-Life.
3. Precession and Nuclear Magnetic Resonance
A. Magnetic moment and torque.
B. Spherical Pendulum and oscillations.
C. Precession and Demonstration of Resonance.
Note: The manual for these experiments is at the experiment station.
Part II. The Nobel Prize Experiments
1. The Charge to Mass Ratio of the Electron. (choose one method)
A. e/m for the electron using the J. J. Thomson Method.
B. e/m for the electron using the K. T. Brainbridge Tube.
2. The Charge of the Electron (another
approach). (choose one method)
A. The Original Millikan Oil Drop Method.
B. Plastic Sphere Method.
3. Particle Scattering.
A. Hard-Sphere Model of Atomic Scattering.
B. Differential Cross Section in 2-D.
Part III. Computer Modeling (Simulation)
1. Rutherford Scattering and
Cross Section.
2. Determination of Critical Mass for Fission.
Part IV. Contemporary Experiments
1. Muon Physics: measurement of the cosmic-ray muon lifetime.
2. Double-slit interference, one photon at a time!
3. Sonoluminescence!
Note: The manuals for these experiments are at the experiment stations.
REQUIREMENTS
1. A total of five laboratory experiments must be completed. Two weeks are given for each experiment.
2. One experiment must be chosen from each of the four categories.
3. The fifth experiment may be chosen from any of the four categories.
4. The laboratory report will be typed, and contain: an introduction, theory, procedure, data, calculations, diagrams, results, conclusions, and a discussion of the results with a complete error analysis.
5. A completed laboratory report is due one week after the experiment is completed.
6. No laboratory report will be accepted after the due date!
Each experiment/report takes up to 20 points. The following is a scale for the total number of points collected.
Grading:
|
85-100 |
A |
|
75-85 |
B |
|
65-75 |
C |
|
50-65 |
D |
|
< 50 |
F |
INTRODUCTION
A little longer than one hundred years ago a very unusual thing happened. Within a period of only ten years, several major advances in physics were developed:
x-rays in 1895,
radioactivity the following year,
the electron in 1897,
quantum theory in 1900 and
special relativity in 1905.
Each of these developments changed the way we view the physical universe. This was the beginning of what scientists now call modern physics.
RATIONALE FOR THE PHYSICS LABORATORY
There are several reasons for including laboratory experience in a physics curriculum. The following list applies to lab in general rather than to any specific course.
1. To gain a better understanding of the physical universe by providing first-hand experience with laws and principles studied in the classroom.
The greatest physicist of the 20th century, the distinctly English gentleman, Paul Dirac said, "I understand what an equation means if I have a way of figuring out the characteristics of its solution without actually solving it." A physical understanding is a completely non-mathematical, imprecise, and inexact thing, but absolutely necessary for a physicist. The test of all knowledge is experiment. Experiment is the sole judge of scientific "truth."
2. To become personally familiar with as much instrumentation and as many laboratory techniques as possible. Broad experience in these areas will enable you to get the maximum benefit from lab courses. It will also be excellent preparation for research in either employment or graduate school.
3. To obtain a feeling for research - as it really is and not as some form of "cook book" procedure. Research involves carefully planning your own experiment, selecting the variables to control in order to best test your hypothesis, and selecting (and modifying when necessary) the apparatus best suited to accomplish this. By its very nature research is difficult--it is trail blazing and you cannot expect a six lane highway. You will make mistakes and you will become discouraged, but if you are patient and work carefully you will be rewarded with a real sense of joy. (This is not sentimentality--it is experimental science at its best.)
4. To acquire an appreciation for the role of measurement in the structure and development of science (of physics in particular). What does it mean to say physics is an empirical science? What is the relation among models, theories, and experimental data? What are we really saying when we claim something is true? Undoubtedly you have some notions (probably somewhat vague) concerning the role of measurement in science; hopefully, they can be clarified and extended. Such considerations are too important to be delegated to a separate philosophy of science course.
5. To develop some skill at scientific communication--both oral and written. Objectivity and clarity will be stressed. Also included here should be an introduction to physics journals and procedures for information retrieval (use of abstracts, etc.).
These laboratory projects help to develop some general intellectual skills likely to be useful in future work. The specific skills comprise both some relatively simple "basic skills" and some more sophisticated "higher-level" intellectual skills.
The basic skills include:
Being able to use operational definitions to relate symbolic concepts to observable quantities. This skill subsumes the ability to estimate or measure important physical quantities at various levels of precision.
Being able to estimate the errors of quantities obtained from measurements. This skill involves applying habitually some qualitative or non-quantitative statistical notions without any resort to excessive mathematical formalism.
Knowing and applying some generally useful measuring techniques for improving reliability and precision. For example, such techniques including making repeated measurements, using independent measurement methods, or applying comparison or "null" methods.