Upcoming Meeting of VIP

I certainly hope you are aware of our next meeting – VIP at VAST in Portsmouth!  I’m sure I’ll see lots of you there. Make sure and make our two different presentations: Friday November 14 at 10:00 AM for our Share Session and Saturday November 15 at 10:00 AM for our Table Top Labs and Lessons. Both sessions held in the Lee room.  With 3 physics related field trips and no fewer than 20 concurrent sessions that should be of interest to Physics and Physical Science teachers, the only problem will be what to choose!

Our annual spring meeting will be held at UVA once again.  The location will be our standard – the physics building, Jesse Beams Laboratory. There is a good web map at http://www.virginia.edu/webmap/. The physics building is #31 on http://www.virginia.edu/webmap/GMcCormickRoadArea.html. You may want to park in #4 on the same map. The date will be March 27th from 9:00 AM – 4:00 PM.  The emphasis will be on teaching our new SOL   Standard PH.7 a, b, c, d, e, f  which states “The student will investigate and understand properties of fluids. Key concepts include: density and pressure; variation of pressure with depth; Archimedes’ principle of buoyancy; Pascal’s principle; fluids in motion; and Bernoulli’s principle.”  So arrive with questions, problems, solutions, labs, and demos!

Notes from last spring meeting

Our last meeting, held at UVA on April 12, was an exciting time. The theme wasPVC-Physics Very Cheap.  Participants did a “make and take” and walked away with a set of Physics Spinners, Stadium Horn, String-wave Polarizers, Hot Air Balloon, Free CD Spectroscope, and a Temperature Vs Temperature Indicator Device! We also held our annual spring elections. Andy Jackson was re-elected president and Tony Wayne was re-elected vice president.  And to top it all off, thanks to donations from a variety of generous venders and the support of VAST, VIP was also able to provide more than $1600 worth of equipment and gift certificates at our spring meeting!!!!! Many thanks go to Tony Wayne who rounded up most of the gifts. You never know what you may miss – so don’t miss March 27! The first two labs presented in the newsletter are two of the projects we built. They are EASY to construct, and of course, Very Cheap!  They are just waiting for a creative mind to make them into a quantifiable physics lab.

Ways to Use V.I.P. Resources

There are so many ways to use VIP. How many you ask? Well here are a few…

First, as I’ve already mentioned, attend our meetings! Attend two fall sessions at VAST and a spring meeting. Secondly, join us on the web. Tony maintains our web presence at www.vast.org/vip  He has past newsletters, links, meeting notices, applets and physlets, and all sorts of stuff.  It’s a great archive of VIP’s history.  Tons of ideas you can pick through.  And third, a very exciting list serve! Ron Revere is our moderator – thanks Ron! You can link to it off of our home page and sign up.  Just like all of VIP, you can’t beat the price – FREE! As of the beginning of October the list serve has had 1029 messages posted.  It is a wonderful place to post a question, suggestion, or seek some information.  I have been so impressed by the professional, courteous, and productive manner in which those 1029 messages have been exchanged.  The only thing to keep in mind, is when you hit “reply” it goes to ALL of us. (Yes, sometimes I forget this part, sorry.)

Physics Poetry Extra Credit – by Tony Wayne
Any combination of 3 cinquains and haikus equals a 2% grade increase on a test. No more than a combination of 6 cinquains and/or haikus can be turned in during a single grading period. You may work with a single partner. Each student will receive a 2% increase on a test per 4 poems.  No more than a combination of 8 cinquains and/or haikus can be turned in during a single grading period

 IF YOU ARE WORKING WITH A PARTNER. All works are to be turned in at the same time. They are due anytime before 3:35 PM on the last day of the grading period.

Cinquain
Your cinquain MUST include a reference to a physics concept or it can be used as a mnemonic aide to help memorize a physics formula or concept. The cinquain is a simple, five line verse form. Its structure follows specific rules:

Haiku
Your haiku MUST include a reference to a physics concept or it can be used as a mnemonic aide to help memorize a physics formula or concept. No points for a Haiku that violates any of the rules.

Note:    I offer this extra credit all year long.  I convert some of the cinquains and haikus into graphics
and display them on my computer's screen saver along with "action" shots of my students in class. Because my computer is connected to my television, the screen saver plays on my television for all my students
to see.

Thanks for the great idea Tony, or should I say….      

Tony
Educator
Creative Idea Sharing
Gratefully I steal his lessons
Physics!

Very Cheap Physics

Physics Spinners

• 7 inches of 5/8 inch OD CPVC
• 8 inches of 7/8 inch OD PVC
• PVC cutter
• Permanent markers of at least 2 different colors

• Cut the 5/8 inch pipe into sections that are 2 ½  inches, 1 7/8 inches, and 1¼ inches long.
• Cut the 7/8 inch pipe into sections that are 3 ½ inches, 2 5/8 inches, and 1¾ inches long.
• Polish the sections of pipe to remove writing.
• Label the ends of the tubes with two different color icons or letters.
• Or ..you might label them with your school’s initials.

Use

Put the spinner on a flat surface.  Use your pointer finger to push down on one end to give it spin about two axis. Birds eye view shown below

• As the spinner spins you will see ONE letter or symbol only.
• For the situation illustrated above, you will see only the letter
• You will see multiple images of the letter P.  The number of  images is equal to Length/diameter. If you pushed down on the V side you would see only the letter V the same number of times.
• This makes a good “nature of science” lab.  A bag of the six spinners and instructions on how to make them spin is all a student needs to get started.  Students can do experiments, make hypothesis, test them etc.  Finding the “pattern” is probably within the capabilities of many students.  Explaining WHY the pattern is what it is…probably a different story. 
• Here is my stab at explaining it.  The explanation has to do with how the tube spins from a push like this.  The end you push down on is going to spin around on the tabletop and it is going to roll about the long axis in the OPPOSITE direction.  The end you don’t push down on is going to spin around on the tabletop and it is going to roll about the long axis in the SAME direction. The end you don’t push stays in contact with the tabletop. The end rolls without slipping on the surface while the tube spins about its center of mass.  The circumference of the circle the ends trace out is P L.  The circumference the end rolls is P D. The tube will roll around L/D times in making one complete spin.  You will see the letter written on the end you push down on every time it comes to the top of its roll.  This is because the surface you pushed down on is moving much more slowly relative to you since it is “counter” rotating – spinning one direction and rolling the other.  This allows your eye to capture its image.  The motion is fast enough for your eye to retain all L/D images that appear in a full spin.  Since they occur at the same place each time, the image is reinforced. The other end is moving so fast the letter is not visible long enough for your eyes to record the image.  PLEASE submit alternate (and probably better) explanations!

Stadium Horn   

Materials

• 2 9 inch long 5/8 inch OD

      ½ ID CPVC pipe

• ½ inch connector
• 3/8 inch drill bit
• ½ inch drill bit
• 5/8 inch drill bit
• Drill
• 35 mm film canister
• small square of plastic grocery bag

• Cut 2 9 inch pieces of 5/8 inch OD CPVC
• Next you are going to drill three holes in the 35 mm film canister and lid

• The hole in the canister side and the hole in the lid are 5/8 inch.  The hole in the bottom end of the canister is ½ inch.
• Take a small square of plastic grocery bag and put it between the lid and the canister and snap on the lid.  The plastic should be taught.
• Drill a 3/8 inch hole in the center of the length of each 9 inch piece of pipe.
• Slide the ½ inch hole in the bottom of the canister on to one of the sections of 9 inch long CPVC pipe.
• Use the connector to connect the two pieces of pipe.
• Make the pipe touch lightly against the grocery back-Not too tight not too loose.
• Put your mouth over the hole in the side of the canister and blow.

• Pitch can be adjusted by covering up the 3/8 inch holes with your fingers while you blow and by disconnecting the two pipes.

Spectral Lines and the Discovery of the Composition of the Sun and Stars

“They said Iron Agaien”
         by Mary Fuller and Andy Jackson

Engage

            Bright line spectra using flame tests and high voltage gas tubes viewed through diffraction grating.

Explore

            Students will draw (using color pencils or crayons) a continuous spectrum produced by an incandescent bulb and selected bright line spectra. 

Explain

• Lecture on the nature and cause of bright line spectral lines.
• Expand to include UV and IR through various demos. (glow in the dark activated by UV, UV beads, IR w/ CBL temperature probes, quinine water)

Explore/Extension

            Students will be instructed to go look at sunlight reflecting off of a white surface and carefully observe and draw what they observe. The student will be asked to theorize why the dark lines of the absorption spectrum are present.

Explain

            Lecture/demo Cecilia Payne-Gaposchkin’s contributions in this field.

Resources and teacher notes

Equipment

            Gas discharge tubes & high voltage power supply, Bunsen burner, salts, diffraction gratings, and GOOD spectrometer. (I use Project Star Spectrometer http://www.starlab.com/psprod.html $55 for 10)

            Students love looking at emissions spectra. A simple worksheet with a rectangle drawn for each sample is all the paper work you have to prepare. Students should label wavelengths and color the full spectrum by looking at light from an incandescent light bulb.  Interesting topics to discuss are what is the wavelength of the reddest red and the “violetest” violet that you can see?  If you have the gas discharge tubes and transformer available, have students look at and color spectra for Hydrogen, Helium, Sodium, Oxygen, and Mercury.  Look at emissions from flame tests for Sodium, Magnesium and Iron.

            After some time looking and coloring, it is time to learn what makes the pretty colors. I explain the simple spectrum of Hydrogen and “hand wave” the rest. In Hydrogen the one electron can be pumped up to, and fall down from, a variety of energy levels producing the discreet separate color lines. The absorption spectrum for our sun can be seen by looking at a bright white sunlit concrete surface.  You have to find the right balance between shade for the viewer’s eye and brightly lit surface.  Of course YOU NEVER LOOK DIRECTLY AT THE SUN.  The absorption spectra is caused by the light traveling through the outer gasses of the sun.  These gasses absorb the same frequency they would emit.  From these absorption lines you can surmise the elements present in the outer gasses of the sun.

            Why the misspelled title? Because when all the other scientists were claiming the sun was made primarily of Iron, Cecilia Payne-Gaposchkin saw something different. “They Said Iron Agaien” but she saw “they said iron agaien”.  {I think this last part is from Richard Panek’s book but I couldn’t find the page again to reference it again.  It is possible I read it in another source.  If you see it elsewhere, please let me know.}

Good Spectrum Resources

Seeing and Believing: How the Telescope Opened Our Eyes and Minds to the Heavens by Richard Panek

http://www.phys.virginia.edu/CLASSES/252/spectra.html - Dr. Michael Fowler of UVA lecture notes on the history of our knowledge of spectra

http://cannon.sfsu.edu/~gmarcy/cswa/history/cecilia.html - History of Women in Astronomy by the Astronomical Society of the Pacific detailing some of Cecilia Payne-Gaposchkin’s contributions.

http://www.cavendishinstruments.com/sapphire.htm for a beautiful color version of the diagram below.

IMPORTANT VIP TOPIC!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 The University of Virginia’s Physics Department has paid for the cost of mailing the VIP newsletter for many years now.  The costs, of course, keep rising and we are currently mailing about 500 copies of this newsletter.  We need to consider the future of this newsletter.  Is a printed version still appropriate? Is posting it on our web site and not bothering with a hard copy the more cost effective way to go?  In the mean time, if this mailing is not of interest to you, or if you are receiving multiple copies at various addresses, please help us by emailing me the name and address that we should remove from the mailing list.

ajackson@