Watching this resources will notify you when proposed changes or new versions are created so you can keep track of improvements that have been made.
Favoriting this resource allows you to save it in the “My Resources” tab of your account. There, you can easily access this resource later when you’re ready to customize it or assign it to your students.
Applications: Ultrasound, Sonar, and Medical Imaging
Ultrasound is sound with a frequency higher than 20 kHz. This is above the human range of hearing. The most common use of ultrasound, creating images, has industrial and medical applications. The use of ultrasound to create images is based on the reflection and transmission of a wave at a boundary. When an ultrasound wave travels inside an object that is made up of different materials (such as the human body), each time it encounters a boundary (e.g., between bone and muscle, or muscle and fat), part of the wave is reflected and part of it is transmitted. The reflected rays are detected and used to construct an image of the object.
illustrates how a ship on the ocean utilizes the reflecting properties of sound waves to determine the depth of the ocean. A sound wave is transmitted and bounces off the seabed. Because the speed of sound is known and the time lapse between sending and receiving the sound can be measured, the distance from the ship to the bottom of the ocean can be determined. This technique is called sonar (originally an acronym for SOund Navigation And Ranging).
Just as ships on the ocean, certain animals, like dolphins and bats, make use of sounds waves (sonar) to navigate or find their way. Ultrasound waves are sent out then reflected off the objects around the animal. Bats or dolphins then use the reflected sounds to form a "picture" of their surroundings (this is known as echolocation).
Assign this as a reading to your class
Assign just this concept, or entire chapters to your class for free. You will be able to see and track your students' reading progress.
light waves and measuring the time between the transmission and receiving the reflection, sound waves and measuring the intensity of sonic boom, sound waves and measuring the time between the transmission and receiving the reflection, or light waves and measuring the redshift of the reflected light
Source: Boundless. “Applications: Ultrasound, Sonar, and Medical Imaging.” Boundless Physics. Boundless, 21 Jul. 2015. Retrieved 28 Aug. 2015 from https://www.boundless.com/physics/textbooks/boundless-physics-textbook/sound-16/interactions-with-sound-waves-131/applications-ultrasound-sonar-and-medical-imaging-469-1647/