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Re: [Phys-L] kinematics objectives

Maybe I should have said "build intuition" rather than "target misconception". Because in many cases, my students come in with no sense of the subject at all. They have no misconceptions about momentum, energy, charge, electric fields, vectors...for all of those things, they are a clear slate, ready for only those misconceptions that I give them :)

But they most certainly do believe that objects prefer to be at rest. And they believe that objects retain a memory of forces that no longer act. The FCI tests both of these notions multiple times. Those particular misconceptions must be attacked.

-----Original Message-----
From: Phys-l [mailto:phys-l-bounces@phys-l.org] On Behalf Of John Denker
Sent: Thursday, May 09, 2013 11:09 AM
To: Phys-L@Phys-L.org
Subject: Re: [Phys-L] kinematics objectives

On 05/09/2013 06:08 AM, Philip Keller wrote:
I am going to reword the section to remove the term "weight" and
replace it with "the earth pulling on the object".

Another good euphemism for "weight" (W) is _"the force of gravity"_ (F sub
g).

=======================

As for simulations: Galileo is called the father of modern science, in
part because he unified -- once and for all -- theory with experiment.
Nowadays, however, there are three components, not just two:

theory experiment

simulation
and
visualization

Computer simulation revolutionized physics about 60 years ago.
Incorporating it into the classroom is revolutionary ... and several
decades overdue. The simulations change how we think about the theory.
They also change how we think about the experiments. Simulations can be
used both as part of the pre-experiment preparation, and as part of the
post-experiment analysis.

And I think they are good for targeting specific misconceptions.

Let's be careful about that.

As I have mentioned previously, in this forum and elsewhere, you usually
get better results from the positive approach (promoting correct
conceptions) than by the double-negative approach (trying to suppress
specific misconceptions one by one).
http://www.av8n.com/physics/pedagogy.htm#sec-miscon

In rare but important cases, a misconception may be so prevalent and/or so
pernicious that it must be confronted. Still, though, this should be
considered the exception, not the rule.

Part of the problem comes from the Anna Karenina principle:
"Every student who gets the right answer gets more-or-less
the same right answer; every student who is confused is
confused in his own way."

That means that even though you can sometimes get away with confronting
misconceptions in a one-on-one teaching situation, it is much less
practical in a classroom situation.

A solid understanding of /one/ correct concept (such as conservation of
momentum) will wipe out thousands of different misconceptions.

As a specific example of what I'm talking about:
I am absolutely appalled by the traditional method of teaching
special relativity. It involves /creating/ misconceptions (aka
paradoxes) that the students would never have thought of on their
own, and then trying to dispel the misconceptions.

In contrast, I recommend telling students that relativity is not weird or
even complicated. In fact, most of what relativity tells us is stuff we
already know. It provides a simplified and unified explanation for things
we would otherwise have to learn in a helter-skelter non-unified way.
http://www.av8n.com/physics/spacetime-welcome.htm

There is a maxim that says "learning proceeds from the known to the
unknown" i.e. from the familiar to the not-yet-familiar.
So I would recommend starting with a simulation of the utterly familiar
case, where there is no chance of a misconception ...
and then gradually expanding the envelope to include less-familiar cases
... at every stage emphasizing how the new situation makes sense in terms
of what is already known, emphasizing the /connections/ between the various
correct concepts.


With rare exceptions, the correct concepts crowd out misconceptions,
rather like the way a healthy lawn crowds out weeds.

There are (so far as I know) no paradoxes in the correctly-stated
laws of physics. To a first approximation, I would be happy to have
students understand the laws of physics so clearly that they cannot
even think of a paradox, and cannot even find the words to express a
paradox.

Bottom line:
-- simulations are good
-- the vast majority of simulations should be organized around
promoting and interconnecting the correct conceptions
(rather than "targeting specific misconceptions")

Reference: http://www.av8n.com/physics/pedagogy.htm#sec-miscon

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