2007-01-22 05:56:30 · 19 answers · asked by northernscoota 1 in Science & Mathematics ➔ Biology
A ducks quack does not echo anywhere...and no one knows why!
2007-01-22 05:59:38 · answer #1 · answered by Anonymous · 0⤊ 3⤋
Sorry to say this but a duck's quack will echo in any covered space, whether it be under a bridge or in St. Paul's Cathedral. The theory is no more than an old wive's tale.
2007-01-23 00:31:58 · answer #2 · answered by Elty82 1 · 0⤊ 0⤋
It's simply not true that a duck's quack does not echo. The Sky TV programme Brainiac took a duck into a tunnel and recorded its quack - you could quite clearly hear the echo.
It seems to just be an urban legend.
2007-01-23 03:41:37 · answer #3 · answered by Daniel R 6 · 0⤊ 0⤋
Of course a ducks quack will echo under a bridge -- just like any other sound.
2007-01-22 06:00:36 · answer #4 · answered by morningfoxnorth 6 · 1⤊ 0⤋
Actually the the ducks quack does echo! you just cannot hear it.
An echo is the reflection of sound waves of a solid surface back towards the source.
when the duck makes a "quack" the sounds wave are long and broken. so cannot reflect as much. The sounds wave that do make their way are so distorted and of such a low intensity that our ears cannot pick then up.
if you use a more sensitive sound detector you can.
2007-01-22 23:38:51 · answer #5 · answered by richard l 1 · 0⤊ 0⤋
Could be that certain types of bridge (underneath) act as a concave acoustic diffraction grating, creating a sound 'spectrum' distrubuted according to its frequencies.
Similar tecniques are used in the construction of auditoria to enhance the sound reception.
Suggested expt: wait till duck enters tunnel. Set of smoke bomb. This triggers camera shutter and makes duck quack. Photo will show up areas of constructive/destructive interference as patterns in the smoke!
2007-01-22 12:37:46 · answer #6 · answered by troothskr 4 · 0⤊ 0⤋
A ducks quack will not echo at all, it is the only audiable sound that does not echo, mainly because of the pitch and tone of the quack itself.
2007-01-22 11:23:22 · answer #7 · answered by Scott Bull 6 · 0⤊ 2⤋
The wave-form of a duck's quack is odd, and lends itself to false absorbtion on most survaces; the easiest way to describe this is to imagine a spiked golf ball being hit - not only is it unpredictable in flight (if it even takes off), but it is unpredictable in its bounce!
2007-01-22 06:05:46 · answer #8 · answered by Modern Major General 7 · 0⤊ 0⤋
I have heard that the quack is supposed to interfere with itself nullifying echoes. I have not had a chance to test the hypothesis.
ADDENDUM:
Tested and disproven.
2007-01-22 06:00:32 · answer #9 · answered by novangelis 7 · 0⤊ 0⤋
Watch out for re-runs of Myth Busters on Discovery Channel. They proved that to be an urban myth.
Of course it echoes.
2007-01-25 07:09:09 · answer #10 · answered by Lemur 1 · 0⤊ 0⤋