Reference Terms
from Wikipedia, the free encyclopedia

Ultrasound

Ultrasound is sound with a frequency greater than the upper limit of human hearing, approximately 20 kilohertz (20,000 hertz).

Some animals, such as dogs, dolphins, bats, and mice have an upper limit that is greater than that of the human ear and thus can hear ultrasound.

Note:   The above text is excerpted from the Wikipedia article "Ultrasound", which has been released under the GNU Free Documentation License.
Related Stories
 


Matter & Energy News
May 29, 2017

Latest Headlines
updated 12:56 pm ET