Hey Ed, Which Is Heavier – Dry or Damp Air?
In this edition of "Hey Ed", Ed discusses which is heavier - dry or damp air in Manual P.
Hey Ed, which is heavier, dry, or damp air? I’m gonna let you know a little secret with this one, when I have some unruly attendees in my classes that is my first move to get them to knock it off and I’ll ask them that and generally when you ask that question people are immediately going to say that wet air, because it has water in it gets heavier and it’s the opposite. If you look at standard air, which is air that contains no humidity, and compare it to air of the same temperature at 50% relative humidity, you will see that that air with more moisture actually weighs less and before the actual argument ensues, I’ll simply ask them, "where do the clouds live?" They're up in the sky, right? And what do things that are less dense i.e. lighter do? They rise! And that’s the way I see it!
In this edition of “Hey Ed”, Ed discusses which is heavier – dry or damp air in Manual P.
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Ed Janowiak is the Manager of HVAC Design Education at ACCA.
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Posted In: Hey Ed, Technical Tips