Is it really true that the quacking sound of ducks does not produce an echo?
Answer:
No, a duck's quack produces an echo, just as other sounds do. An echo is what we hear when sound waves bounce off of a surface and are directed back to our ears.
This is another of those "urban legends" that get into circulation, and seem to keep spreading in spite of the many sites that are set up specifically to debunk them.
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