From Simple English Wikipedia, the free encyclopedia
A sonar machine
Sonar is amachine that uses underwatersound waves to find other objects in the sea. A sonar can work by sending out sound andlistening for echoes (active sonar), like aradar, or by listening for sound made by the object it is trying to find (passive sonar).[1]
thehydrophone or hydrophonearray converts the sound waves into electricity.
The first use of passive sonar was in 1490 byLeonardo da Vinci,[2] when he put a tube onto water and listened. Active sonar was first used in 1917 byPaul Langevin. The wordSONAR was created during theSecond World War as anacronym forSoundNavigation andRanging.[3] This acronym replaced the British acronym ASDIC. The word is now thought by many people as a regular word, no longer as an acronym.
