Belgrade authorities have used sound weapons on the crowd of protesters. The video description has some educational links.

There are lots of videos around.

    • Sylvartas@lemmy.dbzer0.comEnglish
      1·
      13 minutes ago

      Sound is moving air and carries energy. With the right frequency and intensity it could definitely physically fuck you up even if your ears are covered.

      Wikipedia:

      Studies have found that exposure to high intensity ultrasound at frequencies from 700 kHz to 3.6 MHz can cause lung and intestinal damage in mice