Re: [Phys-l] Mass and Energy

["John Clement" <clement@hal-pc.org>]

Part of the problem is the introduction of factor/label before students have
learned what unit conversion means.  There is research evidence that
factor/label prevents understanding.  It is also often not the most
efficient way of doing conversions, especially when only 1 step is required.
Factor label becomes just another incomprehensible procedure for way too
many students.

John M. Clement
Houston, TX

>   a) As a junior, in chemistry class, Johnny learned about unit
>   conversions.
>
>   b) As a senior, in physics class, Johnny knows so little about
>   unit conversions that it is "a barrier to understanding".
>
> It seems that item (b) is a pretty sad commentary on item (a).
>
> In particular, it would seem that "learned" might not be the right
> verb in item (a).  I don't know what did happen, but evidently
> Johnny did not _learn_ unit conversions, not in any useful sense
> of the word.