Why does ultrasound cause pain?

[nuclear-boy]

hi,


at this site:

http://www.amazing1.com/ultra.htm


they have a device called a "phasor pain field generator"

does it really cause pain and nausea etc?
why does it cause any long term effects?
why is there no scientific proof about this anywhere? lol jk







thanks for your help, Alf.

 

[russ_watters]

It's just an annoying, loud noise.