Re: why pseudowork?

[Ludwik Kowalski <KowalskiL@MAIL.MONTCLAIR.EDU>]

I would like to thank John M. who corrected me in a private
message. Yes, I did not think clearly; the v=0 is possible for
the 2 kg block. I was thinking only in terms of two kinds of
collisions, inelastic and perfectly elastic. But there are many
in-between situations and John was probably referring to one
of them. It was a perfectly valid question and I will be waiting
for the answer.

I wrote:

> It seems to me that John M. is asking (see below) "what
> should happen in an impossible situation?". In Jim's frame
> of reference the 2 kg block can not possibly be at rest,
> unless it is not only a collision of two objects.
>
> John Mallinckrodt wrote:
>
> > .... so let me ask you to answer the following question:
> >
> > A 2 kg block and a 1 kg block head toward each other with equal
> > and opposite velocities of magnitude 1 m/s.  After colliding, the
> > 2 kg block is at rest.  How much work was done on the 1 kg block