VtSkier wrote:
Walt wrote:
VtSkier wrote:

From wiki
http://en.wikipedia.org/wiki/Vector_(spatial)
"In physics and in vector calculus, a spatial vector,
or simply vector, is a concept characterized by a
magnitude and a direction."

Yeah. Ok.


Further down the page, magnitude is intentionally
used interchangeably with "length" in effect saying
it's the same thing.

Yes, the magnitude of a position vector is the same thing it's length.

Then "magnitude" = "distance", to which you add
"direction" to define "torque" as opposed to "work".
The only difference.

Um, you lost me around that last curve. WTF?


Think of it this way: I'm testing a binding. I place a boot in the
binding and apply a torque of, say, 50 Newton Meters. The binding
doesn't release. I've just described a situation where there is
torque but no motion. Do you say there is no torque here? If so, how
does one ever test a binding?

You are NOT applying TORQUE to the torque wrench, you are only
applying FORCE of 50 Newtons. There is no TORQUE until there
is movement (of the binding releasing).

As soon as you apply force you are applying torque. The two go hand in
hand, you can't have one without the other. See the definition of
torque: T = F X r . All you need is force and a moment arm, you do not
need motion. I can't make it any clearer.

I don't know where you got the erroneous idea that torque requires
motion, but it's wrong. Trust me. It's wrong. It's not in the
definition of torque.

You are measuring
POTENTIAL TORQUE, which the wrench reads in Newton-Meters
because when the TORQUE happens (by movement) that's what
it will be.

There is no such thing as POTENTIAL TORQUE, at least not in physics.
You are insistent that the torque doesn't exist until something moves,
so you've invented a red herring concept to explain the existence of
something that's obviously there but theoretically impossible in your
belief system. Get out Dr Occam's razor and excise this unnecessary
complication.

When you apply the force, there is also an applied torque. Regardless
of whether anything moves. Get it?

Force implies torque, torque implies force. Where there is one there is
the other *by definition*. And since we agree that it's possible to
have force without motion it is also possible to have torque without motion.


I've been saying this all along except that TORQUE cannot
exist without motion.

Yes, I know that that's what you've been saying.

And I've been saying that every physics text written in the last 300
years disagrees with you.

//Walt
//
//this is why I usually don't argue physics on usenet