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Re: Dew Formation

Yes, this is especially noticeable here, as out car is parked between
the house and a brick wall.

Coming soon -- atmospheric radiation (down welling).

bc, who next time will quantify this effect with his handy dandy Radio
Shack IR thermometer.


Forum for Physics Educators <> writes:

I assume that the colder
air falls to the ground so that by the side windows it is slightly
warmer. However, for the windshields the "ground" is the hood or rear
trunk and is just that much cooler.

In a class taken many years ago, I was led to believe that the top of the
car was radiating into space and the sides into the neighborhood. The rate
of radiation is supposed to depend on the differences of the 4th power of
the temperatures (K^4). The clear night sky is much colder than the
neighborhood and thus the top of the car radiates faster dropping to a
lower temperature producing the conditions needed for freezing. It makes
some sense to me and would love to know if that is still a valid


Ken Fox