FALL 2001 MEETING NOTES

October 26-27

Naval Postgraduate School
Monterey, California

The Northern California/Nevada Section would like to sincerely thank Bruce Denardo and his fellow staff members at the Naval Postgraduate School for their wonderful hospitality last weekend. All phases of the meeting were excellent and we look forward to returning to NPS sometime in the future.

Friday Workshops

"New Teacher Workshop"
Paul Robinson, Lonnie Grimes, Dean Baird

This popular day-long workshop, presented on Friday by Dean Baird, Lonnie Grimes, and workshop leader Paul Robinson was attended by 18 participants from all over Northern California/Nevada. Activities included discussion of the defining the various course levels and the challenges they present (Dean Barid), the importance of teaching physics to a broad spectrum of students (Lonnie Grimes), and teaching tips/demonstrations (Paul Robinson). Teachers received many handouts, complimentary lab manuals, and the always popular graduation present "Goodie Bag" assembled by Stephanie Finander.

"Dramatic Physics Lecture Demonstrations"
Bruce Denardo, Scott Davis, Daphne Kapolka,
Gamani Karunasiri, Kevin Smith, and Don Walters

Dramatic and unusual demonstrations were performed, explained, and discussed.

Friday Laboratory Tours

Lab Tour
"Acoustophoresis and Time-Reversal Acoustics"
Ed Tucholski, Naval Postgraduate School

Friday Evening Social

"Quantum Mechanics of Nanotechnology"
James Luscombe, Naval Postgraduate School

Following the historic trend in miniaturizing electronic components, minimum device sizes will reach 100 nanometers in the near future. This size is significant for two reasons. First, as was explained, in the sub-100 nanometer regime the physical principles upon which conventional electron devices are based will no longer be suitable for device operation. At the same time, quantum effects will come to predominate as device sizes become comparable with electron wavelengths in semiconductors.

Saturday

Welcome and Announcements

Distinguished Service Awards:

Dean Baird - Long time contributer, past officer, awesome web site

Lonnie Grimes - Long time contributor, 90% of students in his schoolin physics classes, modest

Show & Tell:

Ann Hanks - American River College - Cooling of differently colored cans and heating of same in the sun - surprising results

Cheuk Chau - Chico State - Standing wave experiments w/ long spring before introduced to formal labs

Phil Gash - Chico State - The green color on $20 bills is an interference ink made in Santa Rosa.

Bernard Cleyet - Ret. - Demo with vacuum tube triode that has zenon gas and a "box" around the electrodes

Joe Manildi - Watsonville HS - Hover craft

Lou Eptstein - SFCC - Trends in petroleum use in last 20 years

Fred Oswald - Colby Academy, LBNL - Cosmic Ray detector from QuarkNet

Art Fortgang - Mills HS - Lenz's Law demo

Richard Crapuchettes - Balancing demo - c.g. - from simple materials. Simple hydraulic demo. Beats demonstrated on guitar.

Mike Ugawa - St. Ignatius - Dust explosion demo

Paul Robinson - San Mateo HS - Some toys he uses to illustrate concepts

Kimberley Sandstrom - Cal Poly - April 26-27, 2002 - spring meeting information at: atom.physics.calpoly.edu/aapt

Invited Talk 1:

"Time-Reversal Acoustics"
Andrés Larraza, Department of Physics, Naval Postgraduate School

Until recently, focusing of acoustic pulses through media with complex propagation properties had been a very difficult problem. As analog-to-digital converters have become faster, a novel technique called time-reversal acoustics has been able to overcome this difficulty. In a common realization, the time-reversal acoustic technique consists of transmitting an acoustic signal from a point-like source, digitizing the analog signal received by a microphone or a hydrophone, time reversing the signal, and retransmitting it from a nearby source. Applications of time-reversal acoustics are numerous and include medical applications (imaging and lithotripsy), nondestructive testing, underwater acoustic communications and sonar, and counter-mine warfare.

Invited Talk 2"

"Free Electron Lasers of Today"
W. B. Colson, Naval Postgraduate School

Imagine a laser that is continuously tunable over a wide range of frequencies and that can be designed to operate where conventional lasers do not exist. This new kind of laser has already operated at microwave, far infrared, visible, ultraviolet, and even down to X-ray wavelengths. In addition, it can run reliably and efficiently for hours, days, or even weeks with only minor maintenance, producing CW laser light or short sub-picosecond pulses. This is the FREE ELECTRON LASER which contains only the essential ingredients for light amplification by stimulated emission: an external field, the laser light, and free electrons. FELs use a beam of relativistic electrons passing through a periodic, transverse magnetic field to amplify the co-propagating laser light.

Lab Tours:

Rail guns lab tour (Adamy and Snyder, Spanagel 011)
Acoustic detection of buried mines (Muir, Spanagel 025)
Thermoacoustic heat engines (Hofler, Spanagel 036)

Raffle/Business Meeting

 

Contributed Papers

"Fusion Technology at Low Temperatures", Charles Jordan, Foothill College, egonjoe@home.com

There are now refereed papers from SRI and LANL confirming nuclear reactions at low temperatures and I have new results in cavitation driven nuclear fusion processes producing helium in large quantities and 75 watts of extra energy in a light bulb size reactor. I will review the present state of affairs in the investment community and the present understanding of the mechanism.

"Teaching Physics with Micro Electro Mechanical Systems (MEMS)", Cindy Krysac, Department of Physics, University of the Pacific, krysac@artemis.cop.uop.edu Website

A small but developing collection of classroom examples and problems using MEMS will be presented as illustrations of the application of thermal, electrical, mechanical, optical and acoustical physics to an advanced, modern technology. Use of these classroom examples engages students in learning about the emerging technology, emphasizing the importance of a fundamental physics education to the development of such technology.

"Where Does the Plutonium Come From?"

Paul Peter Urone, California State University, ppu@csus.edu

238Pu is used as an energy source in deep space probes. While the technique for the manufacture of 239Pu is commonly known, that for 238Pu is not. There are a number of interesting classroom and homework problems as well as student projects related to 238Pu. Among these are the production techniques themselves, the characteristics and uses of 238Pu, and its biological hazards. I will discuss a few of these in some detail and make suggestions for others.

"The String Machine", Cheuk K. Chau California State University, Chico, CKCHAU@csuchico.edu

During the Spring 2001 NCNAAPT meeting at Berkeley, Don Rathjen of Exploratorium Teacher Institute demonstrated his amazing string machine. With a motor at each end of a string he generated a one-loop standing like pattern. By pinching the string at certain locations, a two-loop, three-loop and four-loop pattern appeared. Did the string change from one resonance frequency to another instantaneously? In this talk we will demonstrate and present an analysis on the string machine.

"Putting: The Prequel", Scott K. Perry, American River College, skparc@home.com Website with several files to download

Before golfers can even begin to worry about the Holmesian capture cross-section of the cup in the middle of a putting green, they must first get the ball to the hole. "Reading the break" on a sloping green can be very tricky making the selection of the proper velocity vector difficult. A computer putting simulation will be discussed along with the results of experiments conducted on local practice greens. A discussion of the apparent paradoxical nature of rolling friction will also be presented.

"Colliding Magnetic Pendula: When is a collision not collision-like?", David Kagan and Chris Gaffney, California State University, Chico, dkagan@csuchico.edu, cgaffney@csuchico.edu

This talk will review the subtle physics of the Newtonian Demonstrator (five colliding balls suspended from strings) and illustrate the key issues by introducing the MagnaSwing which is a Newtonian Demonstrator made with repeling magnets instead of steel balls.

"QuarkNet", Fred Oswald (retired) Napa, NSOH@aol.com Website

Next summer QuarkNet will be offering a three-week shortened course for twelve new teachers at each site.Generous stipends and $250 equipment funds for the next two years are provided for selected participants. AAPT members are excellent candidates for the program. This "paper" is designed to make physics teachers aware of the program, hopefully recruit new participants for next summer's classes, and provide an opportunity for last summer's participating teachers to describe the affect the training has had on their classes.

 

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10/27/01