Why are ultrasound waves used in Sonar?

Q: Why are SOUND waves used in sonars: A: Because sound travels through the water medium better than any other form of energy does. read more

A: Most sonars don't. Sonars designed to detect submarines in open water, which is almost all of them, use frequencies that are well within the hearing range. read more

Sonar. Sonar is used on ships and submarines to detect fish or the sea bed. A pulse of ultrasound is sent out from the ship. It bounces off the seabed or shoal of fish and the echo is detected. The time taken for the wave to travel indicates the depth of the seabed or shoal of fish. read more

Sonar (sound) waves are a type of Longitudinal wave - Wikipedia as opposed to transverse waves like light (electromagnetic). Longitudinal waves oscillate as compression/pressure in the direction of travel through a medium. read more