Spring 2012
Physics 401 is a one semester course intended to give students an introduction to basic laboratory techniques in the context of classical mechanics and electromagnetism. The course consists of a one-hour lecture and a 4-hour lab-period per week.
The primary goal of the course is to introduce students to
basic concepts in experimental physics including:
Ø acquire
basic concepts related to the experiments
Ø
become familiar with modern
experimental instrumentation
Ø
learn how to make reliable measurements
Ø
understand the precision of a
measurement and statistical analysis
Ø
learn how to do calculations with
proper significant figures
Ø
learn how to do data and graphical
analysis
Ø
learn how to write a laboratory report
Ø
learn the advantages and limitations of
computers in experiments
Ø learn how to approach an experiment systematically and think analytically.
Ø
Note: Although only P325 is required for the course, most of
the topics require background in E&M. The lab manual given with each lab
does present the necessary theoretical background to understand the experiment.
If this is not sufficient, students are expected to learn the necessary material
on their own (see Griffiths’ excellent E&M text).
The topics covered include:
A. Instrumentation
1.
Oscilloscopes
2. Digital
multi-meters
3. Signal
generators
4. Data
acquisition hardware
5.
Synchronous detection using lock-in amplifiers
B. Data Analysis/Acquisition Software
1. Origin
2.
Mathematica
C.
Data Analysis Techniques
1.
Statistical and error analysis
2.
Frequency and time domain analysis
D.
Measurements
The
experiments are intended to cover a diverse set of topics including:
1.
Measurements of systems that exhibit linear response
i.
RLC circuits
ii.
Torsional oscillator
2.
Time and frequency domain measurements
i.
Fourier analysis of pulses
ii.
Pulses in transmission lines
3.
Electromagnetic Phenomena
i.
Measurement of electronic charge
ii.
Measurement of magnetic fields
iii.
Studies with microwaves
iv.
Response of magnetic materials to time-varying fields
·
Computers on 2nd floor of LLP have Mathematica,
Origin, Matlab, MS office, LaTex,
etc.
·
OriginPro 8.6 is available at the UIUC Webstore
for free.
|
|
Name |
Office
Hours |
Phone |
e-mail |
|
Lecturer |
Prof.
Eugene Colla 4137 ESB |
Mondays 4:00-5:00 pm in |
office:
333-5772 |
|
|
Laboratory Instructor |
Matthew
Stupca |
noon – 1 pm Monday in 6103 ESB |
office:333-0509 |
|
|
Laboratory Instructor |
Kanuo Chen |
11am –
noon Tuesday in 6103 ESB |
cell:217-898-5975 |
|
|
Laboratory Instructor |
Suerfu |
noon – 1pm
Wednesday in 6103 ESB |
cell:217-979-8224 |
|
|
Laboratory Technician |
Jack
Boparai |
None |
office:
333-2208 |
LLP = Loomis Laboratory of
Physics LSI = Loomis-Seitz Interpass ESB =
Engineering Science Building MRL =
Frederick Seitz Materials Research Laboratory
·
You will have one lab partner for each
experiment. You are expected to rotate partners for every new experiment.
Excused absences follow the
same criteria as Physics 211 excused absences. All the lab sessions are
full, but in extreme cases it may be possible to triple-up, with permission of
the instructor and the lab TA.
Report Structure
All reports should be prepared using a word
processor. Refer to the report preparation guideline for instructions on how to
prepare your reports. Click here
to download guideline.
Here are helpful websites:
LaTeX homepage: http://www.latex-project.org/
LaTeX in Windows: http://miktex.org/, http://www.texniccenter.org/
LaTeX in Mac: http://www.tug.org/mactex/2009/, http://www.uoregon.edu/~koch/texshop/
Cross platform editors: http://www.lyx.org/, http://www.xm1math.net/texmaker/
"Not So Short Introduction to Latex": http://tobi.oetiker.ch/lshort/lshort.pdf
|
|
Day |
Instructor |
Time |
Room |
|
Lecture |
Monday |
Prof.
Eugene Colla |
3:00 -
3:50 PM |
136 LLP |
|
Section L1 |
Tuesday |
Matthew
Stupca |
1:00 -
4:50 PM |
ESB 6103 |
|
Section L2 |
Wednesday |
Kanuo Chen |
1:00 -
4:50 PM |
ESB 6103 |
|
Section L3 |
Thursday |
Suerfu |
1:00 -
4:50 PM |
ESB 6103 |
|
Section L4 |
Thursday |
Matthew
Stupca |
8:00 -
11:50 AM |
ESB 6103 |
|
Week of |
No. Weeks |
Lab Title |
Downloads |
Point Value |
|
January
16 |
|
No lecture (MLK Holiday) and no Labs this
week |
|
|
|
January
23 |
1 |
Introduction to oscilloscope, function
generator, digital multi-meter (DMM), and curve fitting. |
--- |
|
|
January
30 |
1 |
Transients in RLC circuits |
50 |
|
|
February
6 |
1 |
Frequency domain analysis of linear circuits
using synchronous detection RLC lab report should be submitted
electronically not later than midnight of your Lab day. Notebooks should be
submitted in the beginning of the Lab section |
|
100 |
|
February 13 |
1 |
Pulses in transmission lines Frequency
analysis lab report should be submitted electronically not later than
midnight of your Lab day. Notebooks should be submitted in the beginning of
the Lab section |
100 |
|
|
February 20 |
1 of 2 |
Millikan Oil Drop Experiment / Week 1 Transmission lines lab report should be submitted electronically not later
than midnight of your Lab day. Notebooks should be submitted in the beginning
of the Lab section |
--- |
|
|
February
27 |
2 of 2 |
Millikan
Oil Drop Experiment / Week 2
|
100 |
|
|
March
5 |
1 of 2 |
Torsion
Oscillator / Week 1 Millikan oil drop lab report should be submitted electronically not later
than midnight of your Lab day. Notebooks should be submitted in the beginning
of the Lab section |
--- |
|
|
March
12 |
2 of 2 |
Torsion
Oscillator / Week 2 |
100 |
|
|
March
19 |
|
Spring
Break – No Labs |
|
|
|
March
26 |
1 |
Hall
Probe Measurement of Magnetic Fields Torsion oscillator lab report should be submitted electronically not later than
midnight of your Lab day. Notebooks should be submitted in the beginning of
the Lab section |
100 |
|
|
April
2 |
1 of 2 |
Qualitative
Studies with Microwaves / Week 1 Hall probe lab report should be submitted electronically not later than
midnight of your Lab day. Notebooks should be submitted in the beginning of
the Lab section |
--- |
|
|
April
9 |
2 of 2 |
Microwave
Cavities / Week 2 |
150 |
|
|
April
16 |
1 of 2 |
Final
Project – AC Measurement of Magnetic Susceptibility / Week 1 Microwave lab report should be submitted electronically not later
than midnight of your Lab day. Notebooks should be submitted in the beginning
of the Lab section |
Chapter from book by D.J. Craik and R.S. Tebble - SR830 Manual |
--- |
|
April
23 |
2 of 2 |
No lecture, but you are welcome for discussion of the
results, problems etc. Final
Project – AC Measurement of Magnetic Susceptibility / Week 2 |
|
300 |
|
April
30 |
|
Final Project – AC Measurement of Magnetic
Susceptibility / Week 3. This Lab week is reserved to finish the experiments
if it is necessary. |
|
|
|
May
7 |
|
Final week: Final Project Reports due
at 11.59 PM. Reports should be submitted by e-mail. |
|
Total 1000 |
Error Analysis:
This is a short discussion on error
analysis. It, along with subsequent lecture notes, 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.
There are no course textbooks, but we recommend buying or checking out
of the library An Introduction to Error
Analysis by Taylor and/or (for in-depth
information on error analysis) Data
Reduction and Error Analysis for the Physical Sciences by Bevington and Robinson.
Laboratory report
guide:
This short and concise note
discusses how to write your report and some explanation of error propagation.
Frequency and Time Domain Analysis RLC Circuits and Transmission Lines
Part I:
Frequency Domain Spectroscopy
Understanding the frequency
response of physical systems ranging from single atoms to complex condensed
matter systems, e.g. metals, insulators, superconductors and ferromagnets, is essential to understanding the physics of
the underlying interactions. In this lab we will learn about two widely used
techniques for the characterizing frequency response, (1) frequency domain (FD)
spectroscopy and (2) time domain (TD) spectroscopy. The techniques will be
applied to characterize the frequency response of simple linear circuits. In part
I of the lab, you will investigate the dynamics of resonant RLC circuits and RC
filters using lock-in detection.
Part II: Time
Domain Spectroscopy
In part II of the lab, you
will apply time domain (TD) analysis of complex impedance and compare your findings
with FD measurement.
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 University of Chicago. In this experiment,
we will repeat this Noble prize winning experiment within two lab sessions. A
charged oil drop is introduced between two oppositely charged horizontal plates
where its velocity of fall under gravity and its velocity of rise in response
to a suitable electric field are measured. From this data, the charge on the
droplet may be calculated. In order to speed up the measurements, the computer
measures the time and records the data in a spreadsheet file. The data then may
be analyzed in Excel. We have new setups as of Fall
2006! For reference, we also have a copy of the PASCO manual that
came with the equipment.
The Torsional Oscillator
This is a two week lab to
study the transient and driven response of a torsional oscillator.
During the first week, you will
investigate (1) the transient solutions of a mechanical oscillator; and (2)
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.
In the second week, you will
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 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.
As part of this experiment
you will use a Hall probe to map out the field configuration from distributed
current sources as well as from arrangement of permanent magnets.
Part
II: In this
section, you will construct and measure the field for several Halbach magnet geometries. The description of the
measurement is given here.
There is a Mathematica notebook to assist you in the
field calculations. Click here to
download the Mathematica notebook. In addition, I
have included a reference that discusses Halbach
magnet geometries. Click here
for the reference.
Study
of Electromagnetic Wave Phenomena Using Microwaves
Part I:
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) Bragg diffraction.
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.
Final Project –
AC Measurement of Magnetic Susceptibility
Supporting
Material: SR830 Manual, Magnetism-Craik,
Magnetic Properties
Data Sheets
Transients
in RLC Circuit
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
Transmission
line
Simulation
of signal at load
and reflected
signal from various terminations used in the transmission line experiment.
Fourier
Analysis
Excel workbooks on the
Fourier decomposition of a square wave and a triangle wave written by Professor Steve Errede of out department.
Practical
guide to the Excel FFT function including a discussion of its normalization and
an Excel file showing the FFT of the free decay of the damped oscillator and
pure sine waves.
Excel worksheet to accompany
the guide to the Excel FFT function.
The Fourier transforms of a symmetric
triangle wave and a 50% duty factor square wave have no even harmonics. The
reason is often misunderstood. Why no
even harmonics discusses this point.
References on the discrete Fourier transform may be found at the end of the FFT wiki. Or see The Fast Fourier Transform by Brighman, Prentice Hall, 1974.
Millikan
Oil Drop
Note on error analysis in
Millikan oil drop experiment
Error analysis for
Millikan oil drop experiment
Excel templates for analysis
of Millikan oil drop experiment. You should convert these to Origin format for
your lab.
Rise and fall time
analysis for Millikan oil drop experiment
Charge quantization and
magnitude analysis for Millikan oil drop experiment
Torsional
Oscillator
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 325 Damped
Harmonic Oscillator Lecture
Physics 325 Damped, Driven
Harmonic Oscillator Lecture
Physics 325 Periodic
Driving Forces Lecture
Physics 325 Impulse Methods
Lecture
Powerpoint
slides showing various equivalent definitions of the Q of an oscillator
Information about the server, Phyaplportal,
and Netfiles is here.