Physics 401: Classical Physics Laboratory
Course objectives:
Physics 401 is a one semester laboratory course on experiments and techniques
in Classical Mechanics and Electromagnetism. The course consists of a one-hour
lecture and a 4-hour lab-period per week.
Topics of interest include:
- Instruction in experimental physics including data analysis, errors and scientific record keeping: The art to connect experimental data with physics observables!
- Dynamics of electrical and mechanical oscillators in the linear domain.
- Signal and data analysis in the frequency domain.
- Measurements of static magnetic fields, signals on transmission lines, fields in waveguides and cavities.
- Investigation of electromagnetic phenomena in dielectrics, conductors, magnetic materials.
Some tips:
- Before you come to the lab,
- study the laboratory handout carefully. Your learning experience critically depends on being well prepared prior to the laboratory sessions! Solid preparation is also the most efficient approach to a laboratory and will save significant amount of time in carrying out the analysis and writing laboratory reports.
- Answer the prelab questions. They are due at the beginning of lecture.
- Keep two laboratory notebooks. Your laboratory notebook is your record of your work in the lab. Use one notebook for the first, third, fifth etc. labs, and the other for the second, fourth, sixth etc. labs. Your laboratory notebook is submitted with your laboratory report. While your laboratory instructor is grading your report, you will use the other laboratory notebook for your work during the lab.
- The laboratory notebook must be a bound ruled notebook.
- The laboratory report is due at the beginning of the laboratory session of the next week. It will be graded and returned to you the following week in your laboratory session. Thus, you have one week to write a laboratory report.
- Alternatively you can turn in
the laboratory report early for extra credit (1.5 points on the report).
In this case the deadlines are
- No laboratory report or prelab is required for the first laboratory, Introduction to Oscillocope/Function Generator/DMM... All other labs require laboratory reports and pre-labs.
- Keep your laboratory reports and your prelabs to study for the mid term and final.
- Do not miss any laboratory or lecture.
- If you somehow miss a laboratory, consult with your laboratory instructor immediately to do the lab in another laboratory session during the week. Laboratory setups are changed every Friday.
- Consult with your instructors for any problems regarding your reports, prelabs, laboratory schedule, etc. You may email, call and/or drop in to resolve your problems as soon as possible.
Announcements:
Final Exam: May 7th in Loomis 158 from
Grading:
The relative weight between pre-laboratory problem sets, lab-books,
lab-reports, mid-term and final exam are defined as follows:
|
Pre-Lab+Quiz |
20% |
|
Lab Book |
20% |
|
Lab Report |
30% |
|
Mid-Term Exam |
10% |
|
Final Exam |
20% |
Staff:
|
|
Name |
Office Hours |
Phone |
|
|
Lecturer |
Matthias Grosse Perdekamp 401B LLP |
Monday Loomis 401B |
333-6544 |
|
|
Laboratory Instructor |
Jian Xu 4127 ESB |
Monday ESB 6103 |
333-4403 |
|
|
Laboratory Instructor |
Satwik Rajaram 3107 ESB |
Wednesday ESB 6103 |
333-7223 |
|
|
Laboratory Instructor |
Drew Gifford 290F LSI |
Tuesday ESB 6103 |
333-0191 |
|
|
Laboratory Technician |
Jack Boparai 6101 ESB |
none |
333-2208 |
LLP = Loomis Laboratory of Physics
LSI =
ESB =
Students (in alphabetical order):
to be updated...
Lecture and Laboratory Schedule:
|
|
Day |
Instructor |
Time |
Room |
|
Lecture |
Monday |
Matthias Grosse Perdekamp |
|
LL158 |
|
Section A |
Tuesday |
Jian Xu |
|
ESB 6103 |
|
Section B |
Wednesday |
Drew Gifford |
|
ESB 6103 |
|
Section C |
Thursday |
Satwik Rajaram |
|
ESB 6103 |
Experiment Schedule (and links to lectures):
|
Week of |
Week # |
Lab# |
Lab Title (Q: link to quiz - P: link to pre-lab - L: link to lecture) |
|
Jan 17 |
0 |
|
no class this week. |
|
Jan 24 |
1 |
1 |
|
|
Jan 30 |
2 |
100 |
|
|
Feb 7 |
3 |
5 |
|
|
Feb 14 |
4 |
11 |
Pulses in Transmission Lines |
|
Feb 21 |
5 |
10 |
|
|
Feb 28 |
6 |
6 |
|
|
Mar 7 |
7 |
7&8 |
|
|
Mar 14 |
8 |
54 |
|
|
Mar 21 |
9 |
|
Spring break |
|
Mar 28 |
10 |
54 |
Millikan Oil Drop Experiment II In-class Mid-Term Exam on Monday, March
28 |
|
Apr 4 |
11 |
67 |
|
|
Apr 11 |
12 |
22C |
|
|
Apr 18 |
13 |
34 |
|
|
Apr 25 |
14 |
- |
Microwave Cavities Q P L |
|
May 2 |
15 |
- |
No Laboratory, Lecture on Monday May 6 |
|
May 7 |
15 |
|
Final Exam: 158 Loomis 1:30pm to 4:30pm |
|
|
|
|
|
Experiments:
The experiment numbers do not correspond to the week of the semester.
To read Adobe Acrobat or PDF (Portable Data Format) files, you will need the latest version of Adobe Acrobat Reader® (tested with version 4.0). If you do not have it, download it free from here.
Graph papers are available for download. Graph paper is also available in the 401 laboratory.
This is a short discussion on error analysis. Along with the Laboratory Report Guide, it will provide information on how to analyze your data. There are excellent discussions of expressing uncertainty by NIST as well as on statistics and probability from LBL.
Laboratory report guide: 
This short and concise note discusses how to write your report and some explanation of error propagation.
Experiment 1: Introduction to the Oscilloscope, The Signal
Generator,The Digital Multimeter and the Laboratory Personal Computer 
This first lab is to introduce the basic operations of several laboratory instruments by examining the response of various electrical circuit elements to steady (dc) and alternating (ac) applied voltages. These laboratory instruments are the dual-trace digital oscilloscope (HP 54600B), the function generator (Wavetek Model 81), the digital multimeter (HP 34401A) and computer-assisted data acquisition system (based on LabWindows/CVI using National Instruments Lab-PC+ data acquisition board). These equipment will be used in later experiments and therefore it is very important to understand how these instruments function. Although this is the only lab that a laboratory report is not required, it is compulsory to record your results in your laboratory notebook for future reference.
Experiment 5: Transients in RLC Circuits
The aim of this experiment is to study damped oscillations in various RLC circuits. Both linear and non-linear damping are investigated. Although oscillating systems are not restricted to electrical circuits, electrical systems provide accurate, measurable responses in a laboratory. There are some very general characteristics of an oscillating system which are true for the propagation of light or sound waves, the mechanical vibration of a plate, the pendulum, and many other such systems. Therefore, understanding the nature of electrical oscillations would provide better appreciation of mechanical systems in Experiments 6, 7 and 8.
Experiment 6: Transients in a Torsional Oscillator
The aim of this experiment is (1) to study the transient solutions of a mechanical oscillator; and (2) to study other forms of dissipation besides viscous damping or the linear form found in RLC circuits. This experiment will reinforces the concepts from Transients in RLC Circuits. Although, in general, it is more difficult to carry out a mechanical study of resonance, there are several advantages. The motion can be directly observed and studied. There is no need for an oscilloscope. Changes in mass, moment of inertia or spring constant are more obvious than changes in inductance or capacitance. Phase shifts can be seen. Different forms of dissipation can be created and studied. In addition to magnetic damping, which is like the effect of an electrical resistance in an RLC circuit, Coulomb (or dry) friction occurs in mechanical systems. The magnitude of Coulomb friction is independent of velocity. Also, turbulent dissipation can be studied. Turbulent friction is found in the motion of air around a fast moving car or in the motion of water around a boat. Such dissipation can increase as the square (or larger) power of speed. The report on the upgrade of this experiment is in acrobat format and discussed the details of the hardware and software.
Experiment 7&8: The Phase and Amplitude of the Driven
Torsional Oscillator
Parts of Experiment 7 and Experiment 8 (see descriptions below) are selected in this version.
Experiment 7: The Driven Torsional Oscillator
The aim of this experiment is to study both the transient and steady state behavior of a driven harmonic oscillator. Understanding the driven harmonic oscillator is the way to understand many physical systems. The same basic equations apply to electrical circuits, optical absorption, and even the stability of your car. The associated phenomenon of resonance provides a valuable tool for physical measurements. By studying the resonant frequency, line width, strength, phase, and line shape of a resonance we can carry out precise measurements of the motion of a nucleus of an atom (Nuclear Magnetic Resonance) or the stability of a space ship. The driven torsional oscillator can demonstrate all these characteristics in a quantitative fashion. There are several phenomena that can be measured during a limited amount of lab time such as phase and line shape as well as transient "beats" and the steady state response as a function of frequency using viscous, magnetic damping.
Experiment 8: The Phase of the Driven Torsional Oscillator
This experiment is based on Experiment 7, The Driven Torsional Oscillator. The theory section and experimental techniques explained in that writeup should be referred while doing this experiment. The aim of this experiment is to investigate the phase relationship between the driving source and the driven oscillator with and without dissipation, Many things in nature require two numbers to be described. A velocity requires both direction and magnitude, a sound wave or light wave requires both amplitude and phase. For steady state motion these quantities are independent of time. The phase differences between the driving force and either the disk's angular displacement or its angular velocity can be used for at least two purposes. First, even for dissipation so large that no clear peak in the amplitude as a function of drive frequency can be found, the natural frequency can be found by locating the drive frequency where the former phase difference is 90°, or, the latter is 0°. Second, the unique relation between phase and amplitude for a harmonic oscillator with viscous damping will produce a circle on a polar plot. Deviations from such a circular shape indicate deviations from simple viscous dissipation such as studied in Experiment 7.
Experiment 10: Fourier Analysis
This experiment is (1) to carry out Fourier Analysis, by electronically as well as by computer simulation, of various common waveforms and pulses; (2) to relate the results to behavior in nature; and (3) to understand the effects of both linear and non-linear operations on Fourier transforms. We will use the HP54600B's Fourier trasnform function for this experiment. Computer simulation program (FourierSimulator.zip) is written in C using LabWindows/CVI package. The HP application note #243, Fundamentals of Signal Analysis, is an excellent introduction to digital signal processing.
Experiment 11: Pulses in Transmission Lines
In previous discussion of the transient response of circuits to step voltages (as in Experiment 5), we have ignored the time required for the charge to propagate to the various circuit elements. This is justified for those cases where the time scale involved in the circuit is much greater than that involved in the propagation along the wires, but is not possible if one is concerned with times of the order of nanoseconds (10E-9 sec), since the maximum velocity with which a signal can be propagated is that of light, 30 cm per nanosecond. Although we must allow for the complications of these time delays in ordinary circuits at radio frequencies, it is not feasible to treat such a general system theoretically. However, in this experiment, we will try to understand the propagation of signals in a simple circuit: a uniform two-conductor transmission line. The propagation of signals in these lines is described in terms of the velocity of the signal and the characteristic impedance of the line. We will consider only the special case of a lossless line, for which the series resistance and shunt conductance of the line are negligible. In this approximation the signal is transmitted without attenuation, although distortion can still result from variation of the dielectric constant with frequency. This is a useful approximation for short lines and cables used in transmitting signals no more than a few meters. In transmission lines more than 30 meters long, the distortion and attenuation of signals in the line are sometimes a major problem and must be considered in detail. These effects are also discussed.
Experiment 22C: Magnetization Curves and Magnetic Moments
This experiment is divided into 2 different parts: (1) determination of magnetization curves by Rowland Ring method, and, (2) determination of magnetic moments in common ceramic magnets. Rowland Ring method is to familiarize the students with the quantities B and H, and to study magnetization curves and hysteresis loops in an iron sample, wound as Rowland ring. In the determination of magnetic moments, 4 different techniques (gaussmeter method, fluxmeter method, torque method and force method) are used to find the magnetic moment of a ceramic magnet. Also there are 3 demonstration setups: (1) to investigate the magnetic lines of force; (2) to investigate the B-H characteristics of a ferromagnetic material and a diamagnetic material, and, (3) to explore the spin stabilized magnetic levitation using a Levitron.
Experiment 34: Qualitative Studies of Microwaves
The purpose of a set of 6 experiments is to acquaint the student with the properties of electromagnetic waves. These 6 set of experiments are : (1) wavelength measurement; (2) standing waves measurement; (3) polarization; (4) microwave Michelson interferometer; (5) total internal reflection; (6) reflection from a dielectric slab. Microwaves are well suited for this purpose because the wavelength and the dimensions of the apparatus are convenient for bench use. Properties of the radiation, such as its polarization and its reflection by various materials, can also be demonstrated directly and simply. The lab setup is based on the Lectronic Research Labs Microwave Training Kit . This kit provides a convenient source of microwaves with a wavelength of about 3.5 cm.
Experiment 44: Microwave Cavities
The purpose of this experiment is to investigate the various properties of a rectangular microwave cavity. A 3-cm low power microwaves are used (1) to measure wavelength of the microwaves using a slotted line, (2) to determine the cavity resonances, (3) to investigate the magnetic field direction and coupling inside the cavity, (4) to study the nature of the electric field distribution inside the cavity, and, (5) to determine the cavity quality factor Q.
Experiment 54: Measurement of the electronic charge by the
"Millikan" oil drop method
One of the most important physical quantities is the magnitude of the
electronic charge, e. The first precision measurement of the value of e was
accomplished by the American physicist, Robert A. Millikan (1868-1953), who in
1911 reported the results of his oil drop experiment, done at the
Experiment 67: Hall Probe Measurement of Magnetic Fields
Whereas no convenient technique exists for measuring arbitrary electric fields , several techniques are available for the practical measurement of magnetic fields . These include the observation of the force exerted on a current-carrying wire, the emf induced in a rotating coil, the frequency at which certain atomic or nuclear systems exhibit resonant absorption, and the Hall voltage induced in a current-carrying conductor. The latter technique utilizing the Hall effect has the advantages of requiring only a very small probe and very simple instrumentation. During this laboratory, you will become acquainted with the characteristics of the Hall probe. A gaussmeter is an instrument that is designed to measure the magnetic field using a Hall probe. At the later part of this experiment, you will use a commercial gaussmeter to study the magnetic field distributions produced by both a Helmholtz coil and a solenoid.
Experiment 100: Counting Statistics and Data Analysis
In this laboratory exercise you will obtain data which illustrates the property of statistical fluctuations and which can be characterized by general data analysis techniques. In the each of the three parts of the laboratory you will use a Geiger-Müller counter to measure the decay rate of three different radioactive samples as a function of time. The three sets of data will show a source with a constant decay rate, a source with a simple exponential decay rate, and a source with a more complex decay curve. The data obtained in this experiment is analyzed with the spreadsheet program, Excel. Excel is widely available, quick to learn for basics, and familiar to many already. Excel also produces reasonable graphics. A tutorial for basic Excel use is available here.
The next Pre-Lab Assignment:
Note: The assignments are best viewed by Adobe@ Acrobat Reader version 4.0 or later. If you do not have this version, download it free from here.
Lectures:
Very basic instruction in the use of Excel with examples from the Counting Statistics experiment and the RLC experiment is here. Data files referenced in this handout are on the phyaplu server.
Excel workbooks on the Fourier decomposition of a square wave and a triangle wave written by Professor Steve Errede of out department.
Lecture on discrete Fourier transform written by Dr. John Cimbala of the Department of Mechanical and Nuclear Engineering Department of Pennsylvania State University.
Fourier Transforms, DFTs and FFTs
Powerpoint slides of a Physics 112 lecture on complex impedance in AC circuits written by Professor James N. Eckstein of our department.
Physics 112 Complex Impedance Lecture
Powerpoint slides of Fall, 2000 Physics 225 lectures on damped, driven harmonic oscillator, Fourier analysis, and impulse response methods written by Professor James E. Wiss of our department.
Physics 225 Damped Harmonic Oscillator Lecture
Physics 225 Damped, Driven Harmonic Oscillator Lecture
Physics 225 Periodic Driving Forces Lecture
Physics 225 Impulse Methods Lecture
Note on derivation of some formulas in Millikan oil drop experiment and note on error analysis in Millikan oil drop experiment
Error analysis for Millikan oil drop experiment
Server
Information about the server is here.
References:
|
Author |
References |
|
Abraham and Becker |
Classical Theory of Electricity and Magnetism |
|
Andrews |
Optics of the Electromagnetic Spectrum |
|
Atwood |
Electric and Magnetic Fields |
|
Beast |
Electric Fields |
|
Beers |
Introduction to Theory of Errors |
|
Belaney and Bleaney |
Electricity and Magnetism: |
|
Benumof |
Concepts in Electricity and Magnetism |
|
Bevington |
Data Reduction and Error Analysis for the Physical Sciences |
|
Bradbury |
Theoretical Mechanics |
|
Cheston |
Elementary Theory of Electricity and Magnetic Fields |
|
Corson and Lorrain |
Introduction to Electromagnetic Fields and Waves |
|
Cullwick |
The Fundamentals of Electromagnetism |
|
Duckworth |
Electricity and Magnetism |
|
Everitt and Anner |
Communication Engineering |
|
Feynman, Leighton and Sands |
The Feynman Lecture Volumes |
|
Fowler |
Introduction to Electric Theory |
|
Fowles and Cassidy |
Analytical Mechanics |
|
Frank |
Introduction to Electricity and Optics |
|
|
Introduction top Electrodynamics |
|
Harnwell |
Principles of Electricity and Electromagnetism |
|
Harris |
Electrical Measurements |
|
Heald and Marion |
Classical Electromagnetic Radiation |
|
Holt |
Introduction to Electromagnetic Fields and Waves |
|
|
Classical Electrodynamics |
|
Jenkins and White |
Fundamentals of Optics |
|
Johnson |
Electrical Measurements |
|
Johnson |
Transmission Lines and Networks |
|
|
Electromagnetic Waves and Radiating Systems |
|
Kip |
Fundamentals of Electricity and Magnetism |
|
Marion and Thornton |
Classical Dynamics of Particles and Systems |
|
Maxwell |
A treatise on Electricty and Magnetism |
|
Michels |
Electrical Measurements |
|
|
Principles of Radar |
|
Nayfeh and Brussel |
Electricity and Magnetism |
|
Page and |
Priciples of Electricity |
|
Panofsky and Phillips |
Classical Electricity and Magnetism |
|
Peck |
Electricity and Magnetism |
|
|
The Art of Experimental Physics |
|
Pugh and Pugh |
Principles of Electricity and Magnetism |
|
Rabinovich |
Measurement Errors: Theory and Practice |
|
Reitz, Christy and |
Foundations of Electromagnetic Theory |
|
Schwarz |
Intermediate Electromagnetic Theory |
|
Scott |
The Physics of Electricity |
|
Smythe |
Static and Dynamic Electricity |
|
Terman and Pettit |
Electronic Measurements |
|
Topping |
Errors of Observation and Their Treatment |
|
|
An Introduction to Scientific Research |
|
|
Treatment of Experimental Data |
|
Young |
Statistical Treatment of Experimental Data |