the.com/ultrasound
sound so high you can't hear it, drawing pictures of the unborn and the unseen
means Sound at frequencies above the range of human hearing (above about 20,000 Hz), used to image the body, clean objects, and measure distances by bouncing echoes.
from From Latin 'ultra,' meaning 'beyond,' bolted onto plain English 'sound' — literally 'beyond sound,' a 20th-century coinage for the pitches that lie past the ceiling of our ears. The 'ultra-' prefix is the same one lurking in 'ultraviolet,' another wave we can't sense but can put to work.
frequencyAbove 20,000 Hz, past human hearing limits
bat techBats echolocated this way millions of years first
flaw finderUsed to spot cracks deep inside steel
cleaning powerUltrasonic baths scrub jewelry with collapsing bubbles
sonic surgeryFocused beams can destroy tumors without cutting skin