Re: [Phys-L] Figuring Physics solution Jan 2018

[brian whatcott <betwys1@sbcglobal.net>]

It seems that there is a presumption that a permanent [cannot be 
stopped'] force necessarily causes movement. It does not.

On the other hand, a force which may be switched on or off may cause 
motion. Or not!

Brian W

On 1/23/2018 1:44 PM, Todd Pedlar wrote:
> That's the problem with a lot of the language of such questions - the
> phrase "that cannot be stopped" is meaningless.   I just don't know what
> those words add to the context of any particular problem.
>
> On Tue, Jan 23, 2018 at 1:42 PM, Philip Keller <pkeller@holmdelschools.org>
> wrote:
>
> > What is a force that "cannot be stopped"?  I have no idea what that phrase
> > means in this context.  Can anyone give me a definition and maybe an
> > example of a force that cannot be stopped and another example of a force
> > that can in fact "be stopped"?
> >
> > On Tue, Jan 23, 2018 at 2:27 PM, Folkerts, Timothy J <
> > FolkertsT@bartonccc.edu> wrote:
> >
> > > > Concrete example: a 10 newton force which cannot be stopped, bears
> > > directly on a 1000 kg marble block anchored in the substrate rock. The
> > > block cannot be moved.
> > > > What happens?
> > > The 10^3 kg block anchored to the 6x10^24 kg earth accelerates at
> > > 1.7x10^-24 m/s^2.
> > >
> > >
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