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PHYS 195: Waves and Fields

Interference by soap film

Spring 2019

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

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

Instructor: Seth Major, smajor, 4919, G052
Office Hours:

Tuesday 2 - ~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 and Simmons reading (on blackboard)



Thursday afternoons 1:00 - ~4:00 PM with Viva Horowitz in G034

Friday afternoons 1:00 - ~4:00 PM with Adam Lark in G034



  • I have added the derivation of the wave equation (pdf). Have a look at this over the weekend so you can have a sense of what it is and places where you would like clarification.
  • I have posted guide 4 and solutions for all three problem sets.
  • The 2019 "Official 195 Measurement of g" is g = 9.84 +- 0.08 m/s^2.


Course Info:

course syllabus (pdf)

Weekly Guides (pdf):

Guide 1 (solutions)
Guide 2 (solutions)
Guide 3 (solutions)
Guide 4


  • Wolfram Alpha (launches a new tab):
  • Clicker questions from lecture.
  • Our derivation for transverse waves on a string.
  • The Citicorp Center in NYC and the Taipei 101 Tower have tuned mass dampers. A book by Kohn, Katz, and Robertson has a schematic of the Citicorp Center mass. The building is 279 m high and has a period of around 6.5 s.
  • 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. (Requires Flash.)
  • The results are in! The 2019 measurement for g on the Hill is g = 9.84 +- 0.08 m/s^2! (This agrees with the previous average of 9.815 m/s^2. Given the variation in measurements I used the standard deviation of your results for the error.)
  • The masses on springs videos: 1 and 2.
  • 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 physics papers are available to read 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.
  • Here is the Phet simulator on resonance.
  • A XKCD comic on resonance.
  • In class on Friday, February 8 we went through the `late time' or `steady state' solution of driven, damped, harmonic motion. Here are the notes (pdf) for the `brute force' approach of plugging the trial solution and working through the algebra.
  • Millennium Bridge oscillation video.
  • For a review of rotational dynamics see Chapter 10 of HRW.
  • Galileo may have timed the swinging of the chandeliers in the Pisa cathedral. This one appears to be one of the "modern" ones installed in 1587.
  • Here is the PhET spring mass-on-a-spring demo. Enjoy!


Labs (pdf):

Lab Syllabus
The Phys 190-5 Uncertainties in a nutshell and guide to Taylor
The Anatomy of a Notebook
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 (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 15 February 2019

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