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[Phys-l] a different kind of math background quiz



On 12/17/2009 10:41 PM, Jeff Loats wrote:

I'm looking for an online, self-grading quiz that students can use to see if
they have the mathematical background to do well in trig. based introductory
physics course.


The following does *not* answer the question that was
asked ... but list members may find it amusing and/or
useful anyway.

http://www.av8n.com/physics/algebra-trig-quiz.htm

It is emphatically not self-grading. It takes me more
time to grade each question that it would for me to
answer such a question. The instructions say "show
your work" and in many cases I am more interested in
the method of solution than in the final answer.
Many of the questions can be solved in more than one
way.

It's also not all that useful as a screening quiz. You
might _wish_ the students could easily answer questions
of this sort ... but in most cases they can't.

As it says in the preface, some of the questions are
easier than they look and some are harder than they
look. For example, question 3 looks like the most
pathetic of plug-and-chug questions, but really
there are multiple layers to the question, and not
all of them are trivial. Please try the question,
and then grade yourself on the following scheme:
1) cnefr gur jbeq ceboyrz fhssvpvragyl gb trg gb gur
"cyht" fgntr,
2) fbyir bar nytroenvp rdhngvba va bar haxabja,
3) rkgenpg gur fdhner ebbg bs 50 jvgubhg n pnyphyngbe,
naq
4) tvir obgu ryrzragf bs gur fbyhgvba frg.

There are several easy ways of doing step (3). Often
folks who are pleased to accomplish step (3) drop the
ball on step (4).

=======

More generally, the question arises, what is this quiz
actually good for?

For one thing, I fantasize about showing it to the math
teachers and saying it would be nice if the students
could answer all these questions ... answer them them
easily, in less time than it takes to ask the questions
... but often they can't. Is there anything we can do
about this?

Also, you can work through some of the questions in
class, and make the point that it's a character-building
exercise. That is, they shouldn't be too quick to give
up on a problem just because it is unfamiliar or because
it "looks" hard. Once they get into it, they might
discover that it is not nearly as hard as it looks.
Alas this runs contrary to the ground rules they've
learned for taking tests in high school, especially
the supposedly "important" standardized tests, where
it is actually good strategy to skip over any question
that looks hard. Students are understandably confused
and alarmed when you start changing the ground rules
on them.