Re: Apparent weight

[phrp@bigcat.fhsu.edu (Roger Pruitt)]

Raacc@aol.com wrote:
> In a message dated 98-02-14 13:35:36 EST, you write:
>
> << Once our students get this separation of weight from the mg force, then
>  they are far more successful with solving dynamics and statics problems. >>
>
> This is surprising since most texts I've used define weight as mg.  I've just
> looked through these texts that all define W = mg.
>
> Physics, Resnick/Halliday/Krane
>
> Physics for Scientists and Engineers, Tipler
>
> Fundamentals of Physics, Halliday/Resnick/Walker
>
> Engineering Mechanics Statics, Hibbeler
>
> Vector Mechanics for Engineers Statics, Beer/Johnston
>
> Physics for Scientists and Engineers, Serway
>
> What texts define it differently and therefore make statics and dynamics
> problem solving easier?
>
> Bob Carlson
You're quite right. Textbooks do generally define the mg force with
weight. That, of course, doesn't make it right or the best way, but it
is the way that it has generally been done since before I was an
undergraduate. Just defining the mg force as the force of gravity seems
to be helpful at least to our students. There seems to be no problem
with not identifing the mg force with weight and prevents awkward 
explanations later when confronted with "weightlessness."

Roger Pruitt