https://physlab-wiki.com/ 2026-04-18T06:27:34+00:00 https://physlab-wiki.com/ https://physlab-wiki.com/lib/tpl/UChicago/images/favicon.ico text/html 2021-09-27T11:10:25+00:00 Anonymous (anonymous@undisclosed.example.com) https://physlab-wiki.com/physicsdemos/waves_and_optics/acoustics/beer_bottle_tones?rev=1632755425&do=diff Beer Bottle Tones Tones are generated by blowing across the mouth of a beer bottle. Water added to the bottle increases the pitch of the tone made. L3 PIRA DCS 3C20.25 text/html 2021-09-27T11:11:12+00:00 Anonymous (anonymous@undisclosed.example.com) https://physlab-wiki.com/physicsdemos/waves_and_optics/acoustics/fourier_synthesizer?rev=1632755472&do=diff Fourier Synthesizer A nine octave synthesizer may be used to demonstrate the decomposition of functions into a Fourier series. Square, triangle, and saw-tooth waveforms may be easily generated by summing sine functions generated by the synthesizer in the correct proportions. The phase of each channel is also fully adjustable. Waveforms are made visible to the class with a projection oscilloscope. A loudspeaker may also be used. text/html 2022-07-25T14:59:56+00:00 Anonymous (anonymous@undisclosed.example.com) https://physlab-wiki.com/physicsdemos/waves_and_optics/acoustics/limits_of_human_hearing?rev=1658775596&do=diff Limits of Human Hearing A sine generator is used in conjunction with a powered loudspeaker to generate tones at frequencies that challenge the limits of human hearing. A0, speaker on cart near workbench or J1 Setup Connect function generator to speaker (preferably with an integrated amplifier). Set tone frequency between 20 and 20000 Hz (the sonic range). Below 20 Hz, too low a frequency; above 20kHz, too high to be heard. The older the effective age of the ear, the lower the higher limi…