Re: Newton's 3rd law? was Re: inertial forces (definition)

[Bob Sciamanda <trebor@VELOCITY.NET>]

----- Original Message -----
From: Leigh Palmer <palmer@SFU.CA>
To: <PHYS-L@lists.nau.edu>
Sent: Thursday, October 21, 1999 12:11 PM
Subject: Re: Newton's 3rd law? was Re: inertial forces (definition)


> I must ask, how do you account for the momentum component in the
> gravitational field in the laboratory? I know of no term used in
> elementary physics which does this. I am thinking of a term
> analogous to the energy term mgh. It is possible to use the law
> of conservation of energy in the Earthbound laboratory by
> adopting this (do you call it fictitious?) energy term in the
> reckoning. I don't recall hearing about a momentum counterpart.
> Leigh

We have the Force Impulse theorem for that!
This speaks to the effect of external forces on our system.

But when you use this with an inertial force you hide under the table the
fact that this external force does not involve another object.  The
Newtonian Force concept is an interaction between OBJECTS.

Bob

Bob Sciamanda (W3NLV)
Physics, Edinboro Univ of PA (em)
trebor@velocity.net
http://www.velocity.net/~trebor