Ultrasonics refers to sound waves that have frequencies higher than the upper limit of human hearing, typically above 20,000 hertz. These high-frequency sound waves can travel through various materials, making them useful in a range of applications, including medical imaging and industrial testing. One common use of ultrasonics is in ultrasound technology, which allows doctors to visualize internal organs and monitor fetal development during pregnancy. Additionally, ultrasonics is employed in cleaning delicate items, such as jewelry, by using high-frequency sound waves to create tiny bubbles that help remove dirt and grime.