Re: [Phys-L] Energy Concept Inventory

[John Denker <jsd@av8n.com>]

In the context of:
  https://www.msu.edu/course/te/407/FS05Sec3/te802/files/EnergyConceptInventory.pdf

On 07/07/2012 10:35 AM, Antti Savinainen wrote:
> Hence, one could argue that "matter" is not converted to energy; 
> instead mass is. I am aware that matter in this sense can be 
> converted to (other type of) energy in annihilation but this in not 
> the case in this question.

Let's accept that interpretation and explore the consequences.  Suppose
we use this ECI in the usual pre-test / post-test scenario.  If the
student learns to get this question right, I cannot interpret it as
a "gain" in conceptual understanding.  Instead I interpret it as a
terminological technicality.  The student has learned to make a dainty
distinction ... a distinction that would have absolutely no value in 
the real world, or in the physics lab /even if it were correct/.

As a secondary point, I don't accept that the distinction is correct.
Physicists routinely distinguish between "light" and "matter", which
is exactly the distinction involved in the supposedly less-correct
answer.  There is even a series of books called "Light and Matter".

> I doubt  this is a rational basis John was looking for but I am quite
> sure that this is what the author of the test was looking for.

That supports my main point: This is not a physics exam but rather a 
telepathy exam.  Understanding the physics is not good enough;  the
student is required to divine what the test-author had in mind.

> [ECI question 3]  students (e.g. in the International Baccalaureate program) are
> quite used to this kind of questions and they probably   understand
> "surroundings" as the rest of the universe.

Again, consider what that means in a pre-test / post-test scenario.
If the student learns to get this question right, I cannot interpret 
it as a "gain" in conceptual understanding.  Instead I interpret it 
as a terminological technicality. 


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

Let me clarify my objection to ECI question 8.  There is a lot of context.
The context suggests that the objective is to explain why the cold-pack
got cold.  _Technically_ speaking, it doesn't actually say that, which
is significant, because the "best" answer (i.e. the least-wrong answer)
says "the cold pack gains energy from its surroundings" ... which clearly
does not explain why the cold back got cold.

My point is that once again, the test requires the student to choose 
between technicalities and common sense.

This leads me to the really important issue that I forgot to mention in
my previous note, namely hypocrisy.

In particular, I offer a warning:  Those who live by the technicality 
die by the technicality.

It is hypocritical and grossly unfair to demand that students cut the 
test-author some slack on the technically-not-correct physics in at
least two of the questions ... when the test-author is not cutting the 
students any slack on esoteric terminological technicalities in other 
questions.

Students react very badly when the teacher is unfair.  A test like this 
can do irreparable damage to the student/teacher relationship.