Re: 1.5 lambda quiz question

["John S. Denker" <jsd@MONMOUTH.COM>]

At 09:18 AM 7/11/00 -0600, Jim Green wrote:
> >   *) About a third of them said "wavelength".  I gave full credit for
> > this;  if the professor didn't notice, I wasn't going to carp if the
> > students didn't notice.
>
> That is unfortunate.  What is wrong with asking for the correct answer?

Depending on context, there can be many things wrong with insisting on an
exact answer.

1) It is against my principles to hold others to higher standards than I
hold myself.  Since *I* didn't notice the professor's 1.5 lambda mistake,
then anybody else who fails to notice gets a free ride.

Sure, I'll point it out, and we'll all try to do better next time.

2) A similar thought:  Confucius say:  Fool can ask ten questions while
wise man is answering one.  It is absolutely trivial for a professor to
compose quiz questions with so many subtle "gotchas" that the quiz has a
modal score of zero.  But what pedagogical purpose would it serve?

3) In circuit-analysis class, I explicitly teach "the principle of
reasonability".  That is, when analyzing a circuit diagram, you should NOT
assume it is a grab-bag of components thrown together at random.  Instead,
assume it was designed by an engineer with some reasonable level of
competence.  It was designed with some _purpose_ in mind.  Try to figure
out the purpose of the overall system, and the subsystems, and then you
will have a much easier time understanding what the individual components
are doing.

In this case the expectation that the professor was trying to mark off 1.0
lambda not 1.5 lambda is a strong and IMHO reasonable expectation.

4) Last but not least, insisting on the exact answer to tricky questions
teaches people to be nit-pickers.  IMHO this is a Very Bad Thing.

When I'm trying to teach the concept of wavelength, I do not want the
students wasting their time wondering whether the diagram depicts lambda,
or 1.0001 lambda, or whatever.

Tricky questions have their place, but in this particular context (given
the purpose of the course and the level of sophistication of the students)
the 1.5 lambda trickery would have been out of place.