Re: i,j,k -- OK, I get it

[Joel Rauber <Joel_Rauber@SDSTATE.EDU>]

> John is saying I would not have needed to draw it that way.  I could
> have drawn unit-vector-r one half the distance, one-fourth the
> distance, or even 10 times the distance.  I now admit that John is
> correct, and I admit that I have, for many years, drawn unit-vector-r
>  as extending one-sixth the way across.
>
> Misery likes company.  Please tell me that there are many
> others of you
> who would have drawn it the same as I.

Mike, I think you give up a little too easily.  I'm still convinced that
when I say F = 3 i_hat Newtons; I can consistantly think of the Newtons as
either going with the 6 or with the i_hat; you just have to be consistant.
My preference is to follow what John Mallinckrodt said and associate it with
the 3; but I believe you can be consistant doing it the other way.  But
having said that; I draw the unit vector on the blackboard one sixth the
size of the other vector, just as Michael does.  I do this so the students
"see" its size as being unity.  They are too liable to think otherwise if I
drew the unit vector any other way.

Joel Rauber


> Michael D. Edmiston, Ph.D.              Phone/voice-mail:
> 419-358-3270
> Professor of Chemistry & Physics        FAX:
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> Chairman, Science Department            E-Mail
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