Re: Interesting

> ....
>      "Ball A experienced 10 newtons held for 2 seconds
> while Ball B experienced 10 newtons held for 2/10 of a second"
> 
> Thus if you agree with the first statement, then "10 newtons held for
> 2 seconds must equal 10 newtons held for 2/10 of a second"!

And that's where you're wrong. The only sensible variable where time and
force are united is in impulse, and you'll see that this impulse is
different for A and B. The KINETIC ENERGY is identical, but that involves
either mass and velocity (1/2 m v2) or force and distance (int F dx).

The equation for momentum and impulse is given by integrating F = ma over
time, giving

mv - mv0 = int F dt

The term on the rhs is called impulse. For a constant force, and no initial
velocity, this equation becomes:

mv = F t                                                         (1)

So ball A has an impulse of 2 * 10 = 20 Ns and ball B 2/10 * 10 = 2 Ns,
which is NOT equal at all. 

The only statement you can make from the fact that the kinetic energy is
identical is that their kinetic energies are identical. You cannot just
leave out the fact that your particles have different masses, that makes
your statement erronous.

> This leaves the joule system for work in a bit of a muddle...

Not so much the Joule system as your theory. I would suggest reading up (and
understanding) some basic mechanics before making statements that existing
theories are wrong. 

> I know that what I call work is called momentum.

Why then confusing yourself by calling it work? Work done is given by int F
dx and impulse (momentum) by int F dt. That's quite different, don't you
think?

===================================================================
Maarten van Reeuwijk                        Heat and Fluid Sciences
Phd student                             dept. of Multiscale Physics
www.ws.tn.tudelft.nl                 Delft University of Technology