Re: REFRACTION - REFLECTION

["Eugene P. Mosca" <mosca@nadn.navy.mil>]

In an earlier message I said:

> The treatment of this topic in Gene Hecht's  book 
> PHYSICS CALCULUS is fresh and, it seems to me, 
> and improvement over the usual treatment in 
> introductory level textbooks. Check it out.

Leigh Palmer's response was:  
*********************** 
I once taught from the noncalculus version of this textbook. I didn't like
it very much. The attempt to explain Maxwell's displacement current
(without calculus) is an utter disaster. I looked in the Calculus version
just now at the section that was suggested. I don't think it's great, but
there are some good conceptual points. What struck me, however, was a
graph and table on the facing page (p. 947, 1st ed., Table 25.1 and Figure
25.18) of indices of refraction.  The table has no surprises, but the
graph is a shocker. There is dense flint glass with a D index of 1.75, and
fused quartz in the table is (for no apparent good reason) called vitreous
quartz on the graph. If the intention is to confuse, then the author and
editors missed a bet.  They could have used a different synonym, fused
silica, in the table. 
************************

I have not seen the noncalculus version, but I am using the calculus
version of the book since August.  It was selected by a committee, mostly
because some instructors thought the students would find it more readable. 

Thanks for the heads up concerning the "shocker" in Figure 25.18.

Leigh went on to say:  
*********************** 
One might well ask me why I have the calculus version if I don't like the
book.  The answer is easy - the publisher (Brooks/Cole) sent out a bunch
of these books at great expense more or less at random. This practice,
almost universal in the trade now with elementary physics and astronomy
textbooks, must be a rewarding one. I do know that the audience for such
books is guaranteed, and price seems to be no barrier to selection by
faculty who don't have to purchase the books themselves. I, for one,
object to the pricing of textbooks and the unethical (and I would have
thought illegal in the USA)  practice of price fixing.  Have you noticed
Amazon *never* marks down textbooks? I used to tell my Canadian colleagues
that such a practice is illegal in the USA; I now see that I was
incorrect.

Our students are being taken to the cleaners by the publishers and many
faculty don't seem to care. It is a disgrace.  
*************************

I'm not so quick to condemn the publishers.  General physics texts are
expensive to produce, particularly since Saunders began printing Serway's
text in four colors a few years ago.  Also, one or two years following the
release of a new edition sales are dominated by used books which leaves
the publishers without sales (and the authors without royalties).  Are
prices fixed by the publishers or is it that the markup margin allowed for
textbooks much less than that for other books sold by Amazon.com?  My
guess is that the markup margin is too small to allow for discounting.

My original message, which appears at the top of this message, was too
brief.  I should have added:  In Hecht's book there is a more extensive
treatment of the scattering of light by individual molecules than is found
in competing books.  In Hecht's book both reflection and refraction are
explained using this scattering.

Gene