Ultrasonic waves are sound waves transmitted above the human-detectable frequency range, usually above 20,000 Hz. They are used by some animals and in medical or industrial technological devices.Know More
Some ultrasound-emitting devices are used to silence barking dogs without hurting human hearing, because only dogs find the sounds intolerable. Similarly, some medical equipment for diagnosing health complications can produce ultrasonic sounds of 10 MHz and above. Such sounds do not harm human tissue.
Bats use high-frequency sounds to navigate and catch prey. The animals emit ultrasonic waves while moving at high speed and in pitch darkness. When the sounds are reflected back, bats can tell what exactly is in front of them.Learn more about Optics & Waves
Compressional waves are waves that move along the direction of propagation in a back and forth motion. Common examples of compressional waves include sound waves and P waves, which are types of seismic waves.Full Answer >
How Stuff Works explains that sound travels in mechanical waves, and these waves are disturbances that cause energy to move. The energy is then transported through a medium. Disturbances occur when an object vibrates. This vibration is caused by interconnected and interactive particles.Full Answer >
All ultrasonic waves share the common property of being mechanical waves with a frequency higher than the upper limit of the human hearing range. The only difference in physical properties between ultrasonic and sub-ultrasonic waves is that ultrasonic waves cannot be heard by humans while sub-ultrasonic waves can.Full Answer >
Electromagnetic and mechanical waves differ in that electromagnetic waves are always longitudinal and do not require a known medium, while mechanical waves are either longitudinal or compression waves and require a medium. All known electromagnetic waves are also known as forms of light. An example of a longitudinal mechanical wave is a wave in water, while sound is an example of a compression wave.Full Answer >