Crossword clues for hydrophone
hydrophone
Wiktionary
n. a transducer that converts underwater sound waves into electrical signals, rather like a microphone
Wikipedia
thumb|upright=0.6|A hydrophone
A hydrophone ( Ancient Greek ὕδωρ = water and φωνή = sound) is a microphone designed to be used underwater for recording or listening to underwater sound. Most hydrophones are based on a piezoelectric transducer that generates electricity when subjected to a pressure change. Such piezoelectric materials, or transducers, can convert a sound signal into an electrical signal since sound is a pressure wave. Some transducers can also serve as a projector, but not all have this capability, and some may be destroyed if used in such a manner.
A hydrophone can "listen" to sound in air but will be less sensitive due to its design as having a good acoustic impedance match to water, which is a denser fluid than air. Likewise, a microphone can be buried in the ground, or immersed in water if it is put in a waterproof container, but will give similarly poor performance due to the similarly bad acoustic impedance match.
Usage examples of "hydrophone".
Anyone listening with hydrophones or studying a sonar scope would be confused, would judge that a school of porpoises had penetrated the cavern and then gone berserk.
However, the use of super-sensitive hydrophones (designed to eavesdrop on enemy submarines) has recently resulted in the astonishing discovery that the rorquals are amongst the most "talkative" of living beings.
Chief Delaney paced back and forth behind his sonarmen, each of whom were monitoring a specific hydrophone array.
Could be a sub, hears us as something big on his hydrophones, not sure of our course and speed and wants us to answer and give him a line of sight for his tin fish.