See ref to SONAR in Wikipedia. Sound travels faster in a more dense material.
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There's them that knows and them that just thinks they know, whitch are you? Stir the pot and see what rises up. I have catalytic properties I get a reaction going.
If sound is a probigated compression wave, how does it travel in an incompressible fluid. I'm sure the answer is simple but I seem to have had a brain cramp.
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No matter how far you have gone down the wrong path....Turn around!
dolphin's use ultrasonic waves to knock out there pray. I suspect it would be very localised. Sonar and whales operate at very low freq's to communicate over a vast distance. just a few clues into your question.
I was once told by a prominent inventor: (Anything that man has devised was evidenced by nature first)