SCIENCE QUESTION #2

Calvin,

Thanks for your answer.  I understand your observation about the behavior of glasses and clothing when coming in from the cold.  I have seen the same thing.  And I also see the logic of your conclusion from the observation.  But I have another explanation that flows from the same observation. 

Here is an explanation that I see:

Your glasses have much more mass density than your clothing does.  So clothes warm up to the interior temperature quicker than glasses do.  I conclude that both glasses and clothes will condense vapor into moisture as long as they are at a temperature below the 80 degree dewpoint temperature of the air.  But since the clothes warm up faster, they stop condensing water vapor before glasses do. 

It is also true that the glasses are an impermeable mass, so any water that does condense on them will accumulate on the surface and be obvious.  Whereas any water condensing in the clothing will disperse out into the volume of the material and become unnoticeable.

But I contend that as long as that clothing is below dew point temperature, it is condensing water vapor out of the air and depositing wet water in the clothing.  But the quickly rising temperature of the clothing will end the water generating process before enough water can disperse into the clothing to make it feel wet.  

The effect would be like spraying your clothing lightly with a spray bottle.  Within seconds, there would be no perception of wet clothing. 

And also, because the clothing is so permeable, the condensation will take place on so many surfaces that it will be almost thoroughly distributed and dispersed throughout the clothing upon origination of the moisture. 

With the drywall sheet, I can see one scenario where vapor could pass completely through.  Vapor would diffuse into the drywall, reach the dewpoint temperature, and condense into water.  From there, it would move further through the drywall mass until it reached a zone near the other side where it would begin to evaporate.  Then it would evaporate into the air of the cold side.  If the water can evaporate as quickly as it is produced, it may never reach a state of saturation in the drywall great enough to cause decomposition of the drywall.  So, you would have vapor passing through the drywall, but changing phase to water in the mid zone, and back to vapor upon exiting the drywall. 

However, it is also possible that vapor input could overwhelm the evaporative capability of the opposite surface.  If that happened, wetness saturation within the drywall might reach the level of causing decomposition.    

So I want to set up an experiment to test these theories.