Orval Fairbairn wrote:
In article .com,
wrote:

Air is pretty heavy, which is why we can fly. It weighs .078
lb/cubic foot at standard sea level pressure and temperature.
What's
that, about 13 cubic feet for a pound? The air in a room can easily
outweigh the occupants.

Dan

I seem to recall .002378 #m/ft3 as air density at STP.

http://www.engineeringtoolbox.com/24_600.html lists it at 60
degrees F. as 7.636 x 10-2 lbs/cu.ft., or .07636 lbs, a bit less than I
had quoted. STP is at 59 degrees, but the one degree difference doesn't
change the density much.

Dan