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Let's agree on one thing -- calling it simply "gravity" as most
Ok. We can't use either common turn of phrase. What to use? The
problem is that there are two contexts for the use of g. One is
freefall, where g really becomes an acceleration. (I prefer using
a(sub)g instead, but that's another story.) Let us name the case were
g should be an acceleration "freefall acceleration."
The other context is in discussing force, eg, W=mg. It always blows
away my students when I point out that g is not an acceleration
here. (In most elementary problems where this first comes up the
mass is at rest! there's clearly no acceleration.) It is the local
gravitational constant which has units Newtons/kilogram. Thus, I name
g in this context the "local gravitational constant."
(aside: to say that N/kg is the same thing conceptually as m/s^2 isNot quite. This is not a question of units but rather a question of
to agree that torque can be expressed in Joules (N-m). We on phys-l
went through all of that not long ago.)
PS My next tirade will be on usage like "the tension overcomes the
frictional force" or worse, "gravity overcomes friction..."
John E. Gastineau