[Phys-L] Re: A Third law question

[jsd at AV8N.COM (John Denker)]

cliff wrote:
> I think John has it right here.
>
> > The question "where did the force come from" is unanswerable.

Actually I think that part of my answer leaves much to be desired.
Maybe it's narrowly true, but the answers given by others are much
better:
  -- the bowstring suggested by David Willey
  -- the scales and/or foam suggested by Scott Goelzer
  -- the deflection of the wall (and optical lever) suggested by Hugh Haskell.

As for the other part of my answer, namely conservation of momentum, I still
agree with myself about that.  :-)