Breezy;+Doppler+Shift

Doppler shift is used to find fetal heartbeats and project a picture. How it works is pretty simple. The doctor sends out a sound on the machine, and the sound bounces off objects (aka baby) at a different frequency. If you calculate the speed and the returning frequency you can position things inside the body. The gel they put on for the ultra sound is a medium in which the sound waves will carry, because sound waves do not travel well in air.

Bats usage of doppler shift is called Echolocation. Bats make a sound via their nose or mouth, this sound is then reverberated back to them. The bat then uses its super tiny brain to calculate how long it took the wave to come back. The bat determines direction size by how long it takes to hit their right and left ears. The bat figures out the direction the object is moving by pitch. Objects moving toward the bat will have a higher pitch then objects moving away.