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Re: [Phys-l] Motion in 1D, vectors and vector components



A Google search on
"scalar projection"
indicates that some people think that there are at least two kinds of projections of a vector onto another vector. See, for instance,
<http://en.wikipedia.org/wiki/Dot_product>
where a diagram caption reads "|a|*cos(θ) is the scalar projection of a onto b".
This might actually argue in favor of using the word "projection" for what some folks call a "component vector" in that it would help folks learn what a projection really is but it indicates that it is not self-describing to everybody. I like component vector because it is self-describing; its name tells everyone that it is a vector.

For the other item, I think I would rate "array element" higher than "matrix element". I believe I have this prejudice because my first encounter with the word "array" was (perhaps) in a programming context where the first kind of array I encountered was a one-dimensional array whereas my first encounter with the word "matrix" was (perhaps) in a mathematics course where the first kind of matrix that was referred to as a matrix was a two-dimensional matrix.

-----Original Message-----
From: phys-l-bounces@carnot.physics.buffalo.edu [mailto:phys-l-
bounces@carnot.physics.buffalo.edu] On Behalf Of John Denker
Sent: Friday, August 17, 2007 4:21 AM
To: Forum for Physics Educators
Subject: Re: [Phys-l] Motion in 1D, vectors and vector components

On 08/16/2007 04:55 PM, Rauber, Joel wrote:

How about:

Component vector => again I like this since it is self-describing

I have no objection to that, although IMHO "projection" is
more concise, is equally self-describing, and is already
well-established in the math and physics literature.