Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: mriver8 on 03/09/2014 02:27:31
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I'm interested in methods of deflecting/shielding ultrasound up to 3GHz traveling through air as a medium. My search lead me to the study of creating impedance mismatches to affect sound wavess. I'm looking specifically for the acoustic impedance neccessary to act as a shield of sorts for materials with an acoustic impedance around one and a half. Some of my searches have said an impedance of around 7 would suffice however I can not find any papers on such tests, and how various materials affected ultrasound travelling through air as a medium at different frequencies. I'm guessing that there have been tests in this area with military applications which would suffice if readily available. To my knowledge this is the best way to affect sound waves, if there are any other methods please feel free to share.
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I'm interested in methods of deflecting/shielding ultrasound up to 3GHz traveling through air as a medium.
3GHz in air sounded impossibly high to me ,
but apparently the upper limit of ultrasound in air is 5GHz ...
http://physics.stackexchange.com/questions/23418/is-there-an-upper-frequency-limit-to-ultrasound
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No I think the U.S. Government may have had sasers, and tech capable of doing yhis for decades, and the tech is now declassofied but hard to find info on. I'm guessing this because the US Goverment usually has tech for several decades before they declassify it. Usually because they now have stuff way more advanced like the Blackbird.