If you haven't noticed yet, it's spring time and a TON of babies are being born. While this comes as a magical time for parents, it comes as a magical time for physics as well. Before babies are born, while still in the womb, mothers must go to doctors to get ultrasounds. possibly better known as sonograms. A sonogram uses high pitch frequencies to detect and create images of a part inside he body, in this case specifically, the womb! A longitudinal wave (in this case) is sent through the body causing particles to oscillate causing a series of compressions and rarefactions.