On Tue, 25 Dec 2007, RichD wrote:
A few days ago, I was in a room on the third floor, the
window was open, some people were conversating
down at street level. Their words came in, clear as a
bell, almost like being in the same room. I was surprised,
I thought the power would attenuate a lot faster.
Then I wondered if it also works the other way - could they
hear our conversations, just as crisp?
I recall a discussion of optics, and someone remarked:
'I see you, you see me' is pretty much a universal law.
Does that also hold for acoustics?
How well does "I see you, you see me" hold for a telescope? The optical
system is reversible, but that doesn't mean that both ends are equal.
In your example, it sounds like reflection from the next building and the
open windows. Your noise that reflects downwards from the open windows
will make it to street level, but since your room is likely to be quieter
than street level, you're probably talking more quietly than the people on
the street.
--
Timo Nieminen - Home page:
http://www.physics.uq.edu.au/people/nieminen/
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