It is SOund NAvigation and Ranging. Sound is used to navigate, and to detect objects in water. Sonography also has other applications.
There are two main types of Sonar systems, active and passive. In active sonar, a pulse of sound is sent out and the operator waits for echoes. How it works is that, when a sound signal is sent into the water, part of it will be reflected back when it hits an object. The distance to the object can then be determined by measuring the time between when the signal was sent and when the echo is received.
In passive sonar, the operator listens to sounds emitted by the object one is trying to locate. Passive sonar uses the sounds emitted by objects such as ships, submarines and creatures such as marine mammals and fish to determine their location.
We also find sonography used in medicine and industry. The sonogram is a broadly applied investigative medical tool that is non-invasive and wonderfully effective. We also see sonography used in industry to look "through" solids for defects or flaws.
The freqeuncy (or pitch) of the sonar is not generally the factor which is likely to effect wildlife, but the amplitude (how loud it is).
That's a matter of opinion, but we believe that necessity is still the mother of invention ... the strongest motivation that drove the refinement and improvement of SONAR and RADAR had to be the advent of WW-II.
I work for a local side-scan sonar company. 5/4/10 we scanned the image of a shark, definitively, at 1.68m in length. That's around 5.5-6 ft. in length. This was in the York river which is north of the JRB (which I drive across daily to go home). So, they would have to swim past this to get to the York. Basically, to answer your question definitively, yes.
The basic idea behind radar is very simple: a signal is transmitted, it bounces off an object and it is later received by some type of receiver. This is like the type of thing that happens when sound echo's off a wall. However radars don't use sound as a signal. Instead they use certain kinds of electromagnetic waves called radio waves and microwaves. This is where the name RADAR comes from (Radio Detection And Ranging). Sound is used as a signal to detect objects in devices called SONAR (Sound Navigation Ranging).
sattelite with sonar
sonar sonar sonar sonar SONAR
No, the Arctic fox does not use sonar. It is not equipped with sonar.
Sonar is measured in sound
In the mountains i detect a rock with my SONAR.
sonar means '...of, or relating to sound'
SONAR=Sound Navigation And Ranging
The SONAR was invented in 1906.
Sonar is an acronym.