Date: Tue, 24 Jun 2003 01:26:09 -0400 (EDT)
From: "Keith F. Lynch" <kfl at KeithLynch.net>
To: WSFA members <WSFAlist at KeithLynch.net>
Subject: [WSFA] Re: bees on the wing
Reply-To: WSFA members <WSFAlist at keithlynch.net>

Ron Kean wrote:

> But suppose we float the mass inside the truck using a helium
> balloon.  Adding the rubber balloon and the helium adds a bit of
> mass to the total, but it seems like if the mass were no longer
> resting on the floor of the truck, the truck would actually weigh
> less on the truck scale than before.

Indeed it would.  You added rubber and helium, but subtracted the
weight of the air that they displace.  And the air was heavier.

Bees can hover only by pushing air down.  This results in an increase
of air pressure at the floor of the truck which exactly equals the
weight of the bees.  Similarly with a bird, a plane, Superman, etc.
--
Keith F. Lynch - kfl at keithlynch.net - http://keithlynch.net/
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