2008+-+7*+Physics+HP

=America's Next Top Science Rockers!!=

Topics we should learn about/Topics to discuss
1 - How to describe a wave* 2 - types of instruments 3- How can I make my instrument be in tune? 4 - What are Waves and Frequencies?* 5 - Acoustics in general 6 - What is a high pitch vs. a low pitch* 7 - What is the relation between sound frequency and string tension?* 8 - How is sound influenced by the material and the volume?* 9 - How do we created different pitches/sounds?* 10 - What materials resonate? 11 - How do vibrations influence sound and sound quality?* 12 - What affects the sound quality of an instrument? 13 - What ranges can different animals hear and why?* 14 - What is "sound pressure" and how does it work? 15 - How does blowing into a flute create sound? 16 - How does sound move through the air?* 17 - What is the difference between tone and pitch? 18 - How does the shape of an instrument affect the way it resonates? 19 - What is resonance? 20 - What are musical keys? How do we figure them out? 21 - How do we decide placement of materials around an instrument? 22 - What defines an instrument? 23 - What makes a scale? Why does it work that way?* 24 - How do we pick up sound? 25 - What are the ratios of sound frequency between different notes of the scale?* 26 - What are Harmonics and Harmonic Series? 27 - How can we change the timbre? What is timbre? 28 - How does sound travel through other different materials (e.g. water vs. air vs. empty space)? 29 - How do wind instruments make sound?* 30 - What do we use to measure sound?* 31 - How do we match instrument materials to the instrument? 32 - What would qualify as music? 33 - What are overtones? How do they work?* 34 - How can we make instruments?

Notes from class/What we have learned so far
4/3

4/1 -Andrew is amazing at everything plus singing -as wavelength increases frequency decreases: frequency =velocity/wavelength -as tension increases, so does frequency, and also velocity -we don’t need a constant as long as we use correct units; wave/second -flames show sound waves by altering air pressure in tube, forcing gas out in different amounts (Ruben's tube) -for a given length, there’s certain frequencies that match the boundary conditions -higher harmonics =increase in frequency

3/21

3/20 HW: Read 11.7-11.8 Do: Q 16,17, P 29-31, 34 link to honors problems (for those without the right book): http://ronnebergscience.com/physics/documents/waves_sound/ch11%20probs.pdf

frequency is inversely proportional to wavelength tension is proportional to wave speed (positively correlated) -- both go up, both down not correlated = amplitude, distance, how much force used, frequency Possibility = wave speed depends on mass Superposition!!! -- two waves occupy the same space and add Standing waves -- at frequencies of multiple of bass frequency Harmonic series -- more and more standing waves on the string Guitar -- different mix of frequencies based on where you pluck (more/less overtones) can force the strings to have a node when block strings of guitar w/ finger

listened to all different frequencies, mosquito ring

almost finished lab, but not quite. still need to discuss the general ideas we can pull out of it.

3/18 wave properties -period = 1/f, time per wave, time between 2 waves -wavelength = length of 1 wave to original position -amplitude = 1/2 height (or, from center to crest or trough) -speed = speed of wave movement (side to side) -frequency = 1/T, number of waves per time - shape (square, sinusoidal, triangular) -particle movement (up and down, vs side to side) tomorrow: big spring, wave speed, wave shapes/sound. 3/17 Replace this text with all the interesting things we discussed

Who is building what
This is a list of who is building what, so if you are building something similar, you can discuss ideas or problems with them

Wind Instruments
Looking to make panpipes/thumb piano (prob panpipes): Kenny Trombone- like instrument WOO!! - Ana

Percussive Instruments
mbira -sam [before maggie] im looking to make one using metal pipes -- Jason Mbira "thumb piano" -- Margaret "Maggie" I'm planning to build a marimba/wooden xylophone -- Brandon I plan to construct a xylophone out of metal piping- Chengappa xylophone - Yurika copper pipe xylophone - Nathan xylophone - Haeseul

Hybrids/Other
I am working on a software synthesizer controlled by a 2-axis graphical interface. (1 axis pitch, 1 axis volume or waveform) Any practical advice would be greatly appreciated. -- [|stephen hudson]