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Re: weight of a bird in a cage



I also applaud a message which describes an experiment. But why
was my request for clarification (see below) ignored?

brian whatcott wrote:

I salute Jim for this most pertinent account. And I sincerely
hope he is showing only a becoming modesty about the pre
eminent place of experiment, and of experimenters on the
on the rungs of the Physics ladder. ...

After reading Jim's message (see below) I asked:

Are you saying that the net weight of the "box with the
fly inside" remained nearly constant (+ or - the weight
of 0.1 mg) no matter what the fly was doing?

Jim Ealy wrote:

Listmembers;

My nature always says go to the lab when I hear "opinions" (I know that
places me several rungs down THE ladder)

My high school students several years ago made a box from dry-cleaner's
plastic wrap and balsa - total was less than 20 grams about 50 cm by 50
cm. A closed system sealed with tape, after fly was inserted - positive
pressure. We waited until spring to capture one of those large flies
(commonly called - casement flies) that emerge in rooms. They placed the
fly in the "box" and placed it on a top-loading balance: 0.1 mg. There is
no question about what happens (flying, landing, starting off from bottom
or side or top (or repeating after punching holes in plastic for air to
move
in or out as in an open system)). "It" only becomes difficult when we as
teachers try to make "it" more than "it" is.
Jim Ealy
Education by Demonstration