1. Hands-on Science at Pasadena Public Library AnnMarie Hurtado, Librarian June 8, 2015 2. But they dont make music 3. https://sites.google.com/site/physicsdt/sound "Molecule2" by Lookang many thanks to author of original simulation = Juan M. Aguirregabiria author of Easy Java Simulation = Francisco Esquembre - Own work. Licensed under CC BY-SA 3.0 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:Molecule2.gif#/media/File:Molecule2.gif 4. https://vimeo.com/2887685 5. * * * 6. (probably just a faint clanging) 7. (bells? chiming? A hum?) 8. https://www.exploratorium.edu/science_explorer/secret_bells.html 9. High frequency waves (lots of short waves) = high pitch Low frequency waves (fewer long waves) = low pitch http://ffden-2.phys.uaf.edu/211_fall2010.web.dir/Amanda_Harper/FourthPage.html Smaller instrument Larger instrument 10. Lets recap that! Smaller, shorter, faster = higher! Larger, longer, slower = lower! http://ffden-2.phys.uaf.edu/211_fall2010.web.dir/Amanda_Harper/FourthPage.html Smaller instrument Larger instrument 11. Whenever you strike an object, you dont just get one frequency. You get many different frequencies at the same time. If they dont fit a certain mathematical pattern, your brain interprets these frequencies as NOISE. But when several frequencies are mathematically related, they blend together into one recognizable pitch, or musical note. Noise Clear pitch 12. You can put several definite pitches together to make chords! These also follow a regular mathematical pattern. A major triad (a happy-sounding, pleasing chord), from http://en.wikipedia.org/wiki/Major_chord http://www.audiocheck.net/audiofrequencysig nalgenerator_sinetone.php 13. http://bagger288.com/goldenmaster/overtone-series-music-with-the-harmonic-ratio- arpeggiator/ In music, all sound waves have frequencies that are fractions of each other. (Noise is not so carefully ordered or controlled!) 14. The thing vibrating might be a tightly-pulled string, a membrane stretched over a hollow container, or air moving fast through a tube. Or it could just be the whole body of the instrument when you strike it. http://www.bashthetrash.com/Instruments_Intro /How_Instruments_Work_-_Easy.html 15. http://www.bashthetrash.com/Instruments_Intro/How_Instruments_Work_-_Easy.html 16. You can group musical instruments into families by describing what part of each instrument is vibrating. Thinly stretched stuff is struck and vibrates over a round bowl Lips are buzzing, vibrating against each other inside a mouthpiece attached to a brass tube, also vibrating with air inside A wooden reed is vibrating at the top of a long wooden tube, also vibrating with air inside Tightly-pulled string is vibrating over a wooden box with a hole in it 17. Can you guess whats vibrating? String is vibrating when its hit by a hammer, triggered by the press of a key. Then the wood that surrounds the string vibrates, too. The entire wooden chamber is vibrating due to the dry beans bouncing around inside and hitting its walls. Lips are vibrating against each other in a mouthpiece attached to a brass tube, and air is making the whole tube vibrate. A wooden reed is vibrating at the top of a long tube, and air is making the whole tube vibrate. 18. Timbre contains all the other information our brain picks up about a sound, apart from the sounds frequency, amplitude and rate of decay. Two different people can sing the same note and yet you can recognize their voices are different. An oboe and a saxophone (both reed woodwinds!) might play the same note at the same loudness, but their sounds will be different. A saxophone will sound breathy, an oboe sharp or nasaly. This is their timbre. https://sites.google.com/site/physicsdt/sound 19. *Melody *Dynamics *Rhythm 20. Use your finger to make the vibrating part of the string longer or shorter Twist the tuning peg to make the string tighter or looser 21. Beat the membrane closer to the deepest part of the bowl (in the middle) or closer to the shallowest part (near the edge) Twist a tuning peg or press a foot pedal to stretch the membrane tighter or looser 22. Cover or uncover holes in the tube to make the air travel a longer or shorter distance from top to bottom OR: Pull out parts of the air tube to make the tube longer or shorter Blow or buzz harder and faster into the air tube so that you get higher-frequency pitches 23. Vary the size, shape, and thickness of the wooden blocks Curve out the underside of the block in the middle to lower the pitch, and on the ends to raise the pitch the shape of the wood changes the shape of the sound waves that it makes! 24. A glass bottle can be either struck or blown into. It can be either an idiophone (vibrating glass with different densities of water inside) or an aerophone (vibrating air running through a tube and bouncing back when it hits water). 25. When blowing air to make a bottle vibrate, longer means lower If you blow over the top of two different-sized empty glass bottles, the longer bottle will produce a lower sound. The air has to travel a greater distance, so the wavelengths will be longer. 26. But what if you fill several bottles with different amounts of water? Which one will sound lower and which one higher? This is the distance the air travels This is the distance the air travels 27. Now strike the sides of the bottles with a utensil instead. Which bottle will sound lower, and which bottle will sound higher? This bottle is not very full of water, so the water will not prevent most of the glass from vibrating. More vibrations = higher frequency. The water in this bottle will prevent most of the glass from vibrating. Fewer vibrations = lower frequency 28. * * * 29. From HowToons: The Possibilities are Endless by Saul Griffith, Nick Dragotta, and Joost Bonson. Published by HarperCollins Publishers, 2007. 30. * * * * http://mayamade.blogspot.com/2010/07/diy-harmonica.html 31. http://mayamade.blogspot.com/2010/07/diy-harmonica.html 32. http://mayamade.blogspot.com/2010/07/diy-harmonica.html 33. http://mayamade.blogspot.com/2010/07/diy-harmonica.html You move the paper strips closer together? You move the paper strips farther apart? 34. Chordophone Membranophone Idiophone