[Phys-l] disambiguating the terminology

[John Denker <jsd@av8n.com>]

On 02/16/2012 06:10 AM, Ken Caviness wrote:

> Clearly _she_ is not confusing true north with grid north, or grid 
> south with true south.

That illustrates a common category of problems, and also nicely
illustrates the solution.

A big part of the teaching job is to prevent confusion (or resolve
existing confusion).  This is a big part of the research job as well.

Very commonly, confusion arises when the same word is being used 
with two (or more!) different meanings.  Examples of a single term 
with multiple inconsistent meanings include
 -- elastic
 -- organic
 -- adiabatic
 -- heating
 -- generator (in mathematics)
 -- blue

I'm not kidding;  the color that would be called "blue" if you bought
a blue shirt would be called "cyan" in the printing trades.  Additional
weird terminology can be found at
  http://www.av8n.com/physics/weird-terminology.htm

Suggestion:  When you or a student is confused, check to see whether the 
terms are being used consistently.  This sounds simple, but in fact it
remarkably difficult.  It requires seriously racking one's brain.  Smart
people get this wrong all the time ... as is documented, for example, in 
the pathetically confused literature on the definition of "heat".

Obvious suggestion:  When you find a problem of this kind, you can fix it
changing the terminology.
 *) Sometimes the simplest approach is to add adjectives or other qualifiers,
  as in 
  ++ "true north" versus 
  ++ "magnetic north" versus
  ++ "grid north".
 *) Sometimes it is better to find (or coin) completely different
  terminology, as in 
  ++ adiabatic --> thermally insulated or 
  ++ adiabatic --> corresponding states (which implies isentropic).