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PHYS 195: Waves and Fields

Interference by soap film

Spring 2018

Laissez les bonnes ondes rouler! (Let the the good waves roll!)

- from the Livingston, LA LIGO Observatory (at one time)

Instructor: Seth Major, smajor, 4919, G064
Office Hours:

Tuesday 1:30 - ~5:00 PM

Mondays 2 - 4



MWF 10:00-10:50 AM Science Center G041



Halliday, Resnick, Walker, Fundamentals of Physics Extended, 10th Edition (same as Phys 190)

John Taylor, An Introduction to Error Analysis

Kleppner & Kolenkow (now on blackboard) and Simmons reading coming soon!



Tuesday afternoons 1:00 -~4:00 PM with Charles Collett in G030 or nearby lab

Wednesday afternoons 1:00 -~4:00 PM with Viva Horowitz in G030 or nearby lab

Thursday afternoons 1:00 - ~4:00 PM with Adam Lark in G030 or nearby lab



  • Thank you for a great semester!
  • The results of the final are in - the average was 78 with a standard deviation of 14.
  • The 2018 "Official 195 Measurement of g" is g = 9.818 +-0.005 m/s^2.


Course Info:

course syllabus (pdf)

Weekly Guides (pdf):



  • Clicker questions from lecture.
  • We discussed lots of material this semester. Here is a five page (is it possible?) review.
  • For more on the Michelson-Morley Experiment see Wikipedia and and this video.
  • On Soap film intensities. A movie of our demo. Here is a link to much, much more on colors.
  • Two-slit interference and diffraction intensity applet.
  • The video of an interference experiment done at Hitachi by Tonomura Here's a link to a Hitachi website with an explanation of the experiment. The history of this experiment.
  • More slit patterns on hyperphysics.
  • Two-slit interference and diffraction intensity applet.
  • Here is the Phet simulation of interference.
  • Simple Huygens' Principle animations.
  • The Phet lens demonstrator.
  • Burning Mirrors?? Did Archimedes use a mirror (or mirrors) to burn the Roman fleet? Here are translations of some accounts and pictures created centuries later. Here are some links giving some perspective from the physical point of view. There's more on the Siege of Syracuse in these pages.
  • A "guest" appearence of the deceased rapper Tupac Shakur used the technique of Pepper's ghost. See more on ars technica.
  • Snell's law waves, without the reflected wave, with the reflected wave.
  • The electromagnetic spectrum.
  • An animation of an e&m plane wave. Wave of an accelerating charge. Wave of an oscillating dipole.
  • Light! The details if you want to see them - notes on the derivation of the wave equation of electromagnetic fields
  • The interval of time between Earth's magnetic field reversals is on the order of 250,000 years (an average). The reversal is not periodic. NOVA has a brief description. Here's the page of one of the authors on a 1995 paper describing numerical simulations of the B-field generation mechanism.
  • Quadrupole field
  • Notes for the Biot-Savart calculation of the magentic field on axis of a solenoid.
  • Electric motor kits have been distributed. These details include a description of what it is all about and a description of a motor design.
  • The 2018 grade calculator (an excel spreadsheet). Simply fill in your mid-term exam grade, solution set grades (out of 10), and estimates for rest, and the calculator will calculate your estimated grade.
  • The 3D electric field line viewer: Download from here. This is running only on older operating systems.
  • Before break I showed a more careful electric field diagram in class. Here (jpg) it is. This opens in a new window.
  • Phet Electric Hockey!
  • The Doppler shift for light is used in astronomy. Here is an illustration and info on red and blue shifts. The effect is one technique for finding extra solar planets.
  • More on the use of the relativistic frequency (Doppler) shift to find an exoplanet near 51 Pegasus. This technique is lso used to explore the structure of the universe. A page summarizing much more detail on this.
  • The Doppler effect at a train station and as a costume on Big Bang Theory.
  • An applet demonstrating the Doppler effect for sound (requires java).
  • There's a Chladni plate picture in the banner of this web page. Wikipedia has more on Ernst and his plates. Here's a page of his notebooks! Of course, YouTube has Chladni plate videos and there's a 2D flaming (!) demonstration shown in this video.
  • Here is the Phet simulation of interference.
  • Here's the article by Mayo on the energy of waves at sea. For more on ocean waves try this link.
  • Animations of different types of wave motions.
  • Here's the derivation of the equation of motion for sound.
  • The results are in! The 2018 measurement for g on the Hill is g = 9.818 +-0.005 m/s^2! (This agrees with the previous average of 9.815 m/s^2 but disagrees with last year's result of 9.800 +/- 0.007 m/s^2. Given the variation in measurements I used the standard deviation of your results for the error.)
  • The Citicorp Center in NYC and the Taipei 101 Tower have tuned mass dampers. Here's a pendulum in the Taipei 101 Tower. For more specifics see this article and "Wind and Earthquake Resistant Buildings", some of which is on google books.
  • Here's the PhET wave simulation.
  • Here's the PhET normal mode simulation.
  • A reconstruction of the black hole merger event that led to the gravitational wave discovery in 2015. The founders of the experiment won the 2017 Nobel Prize in Physics.
  • More on waves in spacetime: LIGO, interviews with gravity wave folks, and movies of numerical simulations of black hole binary systems.
  • The masses on springs videos: 1 and 2.
  • Here is the Phet simulator on resonance.
  • A resonator exhibit at the Exploratorium.
  • A video of a wine glass orchestra or harp
  • You can see more of the Tacoma Narrows bridge in this video.There's a 2006 American Journal of Physics article by Green and Unruh on a more careful modeling of the Tacoma Narrows bridge. (This link is to the arXiv where many phsyics papers are availabel without charge.) Last year APS News published a piece on this and the authors reminded us that the original accident report pointed out the non-resonant behavior of the bridge.
  • Fun can be had exciting the different modes of a suspension bridge. Here's an example at Messiah College.
  • Check out this comic on resonance.
  • Millennium Bridge oscillation video. See also a BCC program on this
  • In class on Monday, February 5 we went through the `late time' or `steady state' solution of driven, damped, harmonic motion. Here are the notes (pdf).
  • For a review of rotational dynamics see Chapter 10 of HRW.
  • Galileo may have timed the swinging of the chandeliers in the Pisa cathedral. A picture of the ones installed in 1587, at History of Science at UO.
  • Here is the PhET spring mass-on-a-spring demo. (Updated link) Enjoy!


Labs (pdf):

The Phys 190 Uncertainties in a nutshell and guide to Taylor
Lab 1: Simple Oscillation
Lab 2: Moving Away from Simple Oscillation with a Pendulum
Lab 3: Measuring g with a pendulum
Lab 4: Resonance
Lab 5: Standing Waves new version (8.9 MB)
Lab 6: Speed of Sound
Lab 7: Coulomb's Law
Lab 8: Electroscopes
Lab 9: B-field mapping
Lab 10: The q v x B force and the electron's charge to mass ratio
Lab 11: Snell's Law
Lab 12: Interference and Diffraction


Last modified 18 May 2018

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