Re: (dv/dt) terminology: opportunity for improvement

[Larry Cartwright <exit60@CABLESPEED.COM>]

I don't believe that a new name is going to improve understanding,
John.  The main problem with students' first encounter with dv/dt is
that it is usually part of their first encounter with magnitudes and
directionality in 3 dimensions, additionally complicated by the concept
of rate of change.

Up to the point of introducing vector-a, their experience with
directionality has typically been pretty simple and one-dimensional:
up-down, increase-decrease, forward-backward, left-right, etc.  They
have come to expect the universe to continue to comply with such
comforting simplicity; then suddenly, ba-da-bim ba-da-boom, here comes a
quantity where "positive" sometimes implies increasing speed and
sometimes implies decreasing speed and sometimes results in no speed
change at all.

Dealing with acceleration and force and impulse and momentum, and all
that comes tumbling out of the associated physics, requires a leap of
intellectual maturity and an entirely new level of insight.  I don't
believe there is any vocabulary change that can be substituted for
maturity and insight.

Best wishes,

Larry

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Larry Cartwright     <exit60@cablespeed.com>
Retired (June 2001) Physics Teacher
Charlotte MI 48813 USA
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Lord, preserve us from the excesses of those
who would do us harm; and preserve us from
the excesses of those who would protect us.
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"John S. Denker" wrote:
> Hi Folks --
>
> A) In physics, we need a name for the quantity (dv/dt).
> It's the same quantity that shows up as (F/m) in Newton's
> second law.  We like to use reference frames that lack
> this quantity.  [snip ...]

This posting is the position of the writer, not that of SUNY-BSC, NAU or the AAPT.