Ultrasound
Infrasound is always smaller or lighter than ultrasound. For example: infrasound can be the sound of a paper clip hitting the floor, and ultrasound can be the sound of two planets colliding.
Infrasound refers to sound waves with frequencies below the range of human hearing (below 20 Hz), while ultrasound refers to sound waves with frequencies above the range of human hearing (above 20 kHz). Infrasound is used in monitoring seismic activity and animal communication, while ultrasound is used in medical imaging, industrial cleaning, and pest control.
Sonic infrasound is a sound too low for humans to hear, below 20 Hertz. Ultrasound is a sound too high for humans to hear, above 20,000 Hertz.
Usually infra red, but I have seen some that use ultrasound.
because ultrasound is more safer than audible sound.
by infra sound....
Sound below 20Hz is considered infrasound, while ultrasound typically refers to sound frequencies above the human hearing range (above 20kHz).
Ultra Sound
Ultrasound is typically performed by a trained ultrasound technologist, it involves using sound waves to get an image of the reproductive system.
"Sound" is a mechanical wave traveling through a medium. Ultrasound is sound, but its frequency is higher than humans can hear.
Endorectal ultrasound (ERUS) is a procedure where a probe is inserted into the rectum and high frequency sound waves (ultrasound waves) are generated
Just to give some clarity, ultrasound doesn't travel faster than sound. It simply resonates at a higher frequency than normal sound. Sound in a lighter atmosphere, or light travels faster than ultrasound.