DL-Waves

Demo - Doppler Sim.  You can simulate moving source and moving observer Doppler.  You can show shock waves

Demo - Doppler by Twirling a speaker around your head.  I demonstrate both moving source AND moving observer!! (jk)

Demo - Diffraction Patterns with a laser.  Double Slit, multiple slit, and single slit.

Demo - Diffraction Grating Glasses to demonstrate Atomic Spectra (Or to demonstrate diffraction gratings.)  You can see the first and second order IRL  (Just not on this video)

Demo - Finger Bells - Metallic objects have vibrations we can't normally hear unless there is a mechanical means through a sold object (A string) to get the vibrations into our ears.  Don't laugh - you really have to try it.  These little pieces of coat hanger sound like giant church bells.  You can do this with big spoons and forks and pot lids.

Demo - FFT and Sound Spectrum - You can see what frequencies make up a particular sound.  Why a trumpet, a voice and a flute all sound different even if they are playing the same note.

Demo - Standing Waves on an Elastic String.  I use the Arbor oscillator thing to get different frequencies of standing waves.  I tune the string so the fundamental is 10 Hz, and have the students predict the frequencies of the next three harmonics.  Then I put a strobe light on it (after inquiring first if that is safe) and you can freeze the standing waves.

Demo - Wine Glass Resonance - Have the students predict what happens when you put more or less water in the glass.

Demo - Polarized Light - a few cool demos - rotating the filters, optical activity, stress and optical activity, birefringence.  I forgot to do a cool one - put the big polarizers at 90o to each other, and put a little polarizer in the middle at 45o and you will see that the light can go through the three polarizers.

Demo - Rubens Tube - The flames interact with the sound waves.  I use the speaker and have the Test Tone Generator sweep from 300 to 800 Hz, I have a kid play the trumpet into the other end.  You can sing into it as well.

https://www.youtube.com/watch?v=a9ggyvCR3w4 - Music

https://www.youtube.com/watch?v=omMzPvgU3P8 - Singing

Demo - Overtone Series on a Pennywhistle (both ends open - so 1, 2, 3, 4x the fundamental) and panpipe (one end closed, so 1, 3, 5, 7x the fundamental)

Demo - Stereo Laser with Musical Intervals - I use the test tone generator to go through the musical intervals and use the laser to make Lissajou patterns on the screen.  These are slightly out of tune because test tone generator uses an even tempered scale.

Demo - Stereo Laser Light show with music.  (Peter Hollens stuff on youtube is perfect for this system)

Demo - The Hot Chocolate Effect - bubbles in water make it more easily compressible, and decrease the speed of sound as evidenced by the tone a column of water makes when you strike the bottom of a beaker.  (Martin Gardner - Scientific American)

Demo - The History of Wind Instruments - a Schtick I got from Pat Canan - the legendary Physics teacher at Corvallis High School.  You can make a simple reed instrument with a straw, and play it to make a major scale.  I cheat - not only do I cut off the straw, but I can influence the tone to keep the scale in pitch with my tongue and lungs.  Not sure exactly how.  Play around with it.

Demo - The Big Flame Pipes - a 4 inch PVC pipe will resonate if you place it (carefully) over a Meker type burner.  I have two pipes and I play them separately, and then together to make the world's loudest beats.  Good fun.  Try not to touch the PVC to the burner.

Demo - Boomwhackers.  It's the air in the tube that makes the tone - it's what is resonating.

Demo -  Two Source Interference Patterns with sound -  When you walk round the room when there is the same pitch coming out of two speakers some distance apart, you have places where the sound is louder, and places where it is quieter.  A PhET demo of two source interference patterns illustrates why.

Demo - Two Source Interference by Moving one of the sources - Two speakers - set up a wave that's like 0.5 m long, (686 Hz) and move one speaker closer to the listener by 0.5 wavelength, 1.0, 1.5 and 2.0 Wavelengths.

Demo - Beware the Undertone!! - I use the dual function generators in Test Tone Generator to show beats as wah wahs, and then play 200 and 300 Hz at the same time to hear a beat frequency that is present as an undertone.

Demo - Dispersion - I get a beam of sunlight to go down the hall outside the room.  (I put a mirror on a stool outside) and I use a prism to make rainbows.  Have the kids figure out which light refracts more - the red or the blue.

Demo - Refraction - Laser enters water and bends.  You have to put something like milk in the water, and dust in the air.  I use lycopodium powder.  This is best if you put a camera on it and project the image on the big screen.

Lab - Index of Refraction - Students use simple distance measurements to calculate the angle of incidence and the angle of refraction and then calculate the index of refraction of the water.  Students struggle with this.

Lab - Waves Lab - Basic concepts like wavelength, wavespeed, and frequency frequency.  I do a cool superposition element in the hall with cups.  (Video to the right  Watch this video: https://www.youtube.com/watch?v=QjukfQttKAQ to see what it looks like)  

More at the website:  https://sites.google.com/a/ttsd.k12.or.us/tuhsphysics/home/htp-physics-g/wavesandsound/g-waves-lab

Lab - yupyup