Jump to navigation
Sound waves that have a very high frequency are called ultrasound or ultrasonic waves. These sounds are so high that humans can't hear them. Dogs and bats have a higher hearing range than humans and can hear some ultrasonic waves.
Ultrasonic sound waves are made by electrical devices (like a loud speaker), which change electrical signals into sound waves.
A receiver compares the length of time it takes for the ultrasound waves to be detected. The longer the time it takes for the wave to reach the receiver the deeper into the body the wave has gone. This information is then used to build up a picture of the internal strutcure of the body, which is then shown on a visual display, like a computer screen.
You can find out more here:http://www.s-cool.co.uk/gcse/physics/uses-of-waves/revise-it/uses-of-sou...
Hope that helps :)
hwzt mdara jack