Re: [Algorithms] rather curious

[<ro...@do...>]

Jeff Lander  wrote:

>Man, we are all working late tonight.  On a sunday, that's kinda sad.

Nah,  I spent a pleasurable day listening to a free concert by the San
Francisco Opera in Golden Gate Park, and am so wiped out by sunburn
that sitting in front of the tube and pontificating on physics is an
entirely appropriate activity.

>But to drag this back to algorithms, your use of Newton's gravitation law is getting you into trouble.  
>

>Realize that the only thing that effects when two dropped objects hit the ground
> is the acceleration of those objects.  Force doesn't enter into it yet.  

Actually, in most developments of the logical foundations of physics
that I've seen I think that  "force" isnot well defined.  In the way I
was using it, in terms of the "four forces",  it refers to a type of
"interaction".

>....
>So you can see that a body of any mass will hit the earth at the same time.  
>The difference due to the original gravitation law is that a more massive body
> will hit the earth with more FORCE and make a bigger dent.
>

Here, I think your use of "FORCE" is not appropriate.  The two bodies
fall under the same acceleration, so fall for the same time duration
and hit the earth with the same speed, but the more massive body has
more kinetic energy and more momentum, so makes a bigger dent.