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Re: [Phys-l] definition of weight



In the context of
http://www.av8n.com/physics/weight.htm#main-instrumental-def

On 11/02/2006 02:25 PM, Rauber, Joel wrote:

definition of weight found in the above reference is contrived (for good
reason) to agree with "what the scale reads" as interpreted in section 9
of the reference.

That depends on what you mean by "agree".

There is a difference between "agrees to a good approximation"
and "agrees by definition".

BTW I think the contriving happens the other way around. I claim
that some scale manufacturers contrive their scales to agree with a
careful definition of weight. In support of this claim I point out
that many scale manufacturers contrive to measure mass, not weight.
This should make it clear that I have *not* contrived my definition
of weight to agree with "whatever the scale reads" -- not by a long
shot.

========

One weird problem is that the phrase "operational definition" is
practically a cliché. As soon as somebody says "operational" the
temptation is to say "operational definition".

We need to find a way to talk about something that is operational
but not definitive.

There are lots of things (including weight) that are well approximated
this-or-that well-chosen operational procedure. I don't have a problem
with that.

I just don't want to be forced to treat as definitive the first
operational procedure that crawls into view.

Operational does not necessarily imply good.
Operational does not necessarily imply bad.
Operational does not necessarily imply simple.
Operational does not necessarily imply definitive.

Oftentimes the definitive procedure is not simple, and the simple
procedure is not definitive.