[Phys-L] Re: In the Private Universe

[rlamont <rlamont@POSTOFFICE.PROVIDENCE.EDU>]

A much simpler approach is to have them imagine standing next to
fireplace. When they face the fireplace the radiation hurts the
skin on their face. When they turn around their face feels cold.
That can be easily related to the tilting of the North Pole
toward and away from the sun.

Bob at PC

> -----Original Message-----
> From: Forum for Physics Educators [mailto:PHYS-
> L@list1.ucc.nau.edu] On Behalf Of John M Clement
> Sent: Thursday, February 24, 2005 12:22 PM
> To: PHYS-L@LISTS.NAU.EDU
> Subject: Re: In the Private Universe
>
> One of the things that has been ignored in discussion of the
seasons
> is that it is a cognitively difficult thing to understand.  The
> drawings in the book are probably red herrings.  While they may
> confirm the naive idea that distance is the primary factor, it
is very
> doubtful that they actually cause the idea.  The idea of
distance is a
> concept that students already bring to the table, and they know
that
> distance from a hot object changes the amount of heating you
> experience.  This is the simple natural explanation and as a
result it
> forms a powerful misconception.
>
> The idea that the angle changes intensity of the sunlight per
area is
> a 3 variable situation.  Accordingly students who are not at
the
> formal operational level will have extreme difficulty with it.
The
> video shows a teacher just explaining it.  That is also a
primary
> source of difficulty.  By presenting the concept first without
the
> necessary exploration, the students will not be able to make
sense of
> it.  Remember, the learning cycle must have exploration,
term/concept
> introduction, application in that precise order.  Now the age
at which
> this is generally done, 10+, is ok because it is possible for
students
> to be at the formal operational level, but remember that only
20% are
> at that level upon HS graduation, and the number is somewhat
smaller
> at 10+.  The development of formal operational thinking takes
time, so
> the seasons may be better tackled at a later age.
>
> A useful thing would be to have a model of the earth where the
> students could observe the amount of light intensity/area.  I
would
> propose a globe with either a light sensor imbedded in it
attached to
> a meter, or a translucent section that provides light in the
interior,
> and a peephole that students could observe the light intensity.
Then
> students could see the effect of the angle.  Then they could
explore
> how the angle and the illumination changes with the seasons.
>
> John M. Clement
> Houston, TX