On Jun 17, 10:57*pm, lu6etj wrote:
On 17 jun, 21:30, Cecil Moore wrote:





On Jun 17, 7:00*pm, Keith Dysart wrote:

An ideal conductor has
zero resistance, so current can flow without voltage in an ideal
conductor.

Quoting "Fields and Waves ...", by Ramo and Whinnery: "A perfect
conductor is usually understood to be a material in which there is no
electric field at any frequency. Maxwell's equations ensure that there
is then also no time-varying magnetic field in the perfect conductor."
How does one go from zero current to a non-zero current if the
magnetic field is prohibited from varying (changing) with time?
--
73, Cecil, w5dxp.com
An ideal conductor has
zero resistance, so current can flow without voltage in an ideal
conductor.

Inertia first Newton law applied to the free electron lttle balls
perhaps?
Now, if at first of experiment little balls was at rest, how do they
set in movement without a force? Tell us.
.....
Keith, OM, *if you do not make the rope experiment, *make this another
simple one = *get from Radio Shack a long, long lossles TL, (with
vf=1, why not?), 6*10^8 meters long it is good, open or short ended
(it does not matter). Connect it to your 100 W rig, key for a one
second the TX full CW power, inmediately disconnect the TL and touch
the connector with your fingers. Just count: tree, two, one, ¡zero!.
If after "zero" you still with the connector in your fingers without
blink, then reflected waves really have not too much reality... have
some ointment for burns, may be the boys are right.) (sorry, do not
be angry with me I am practicing translate some creole humor to
english :D *)

73 Miguel LU6ETJ- Hide quoted text -

- Show quoted text -

Good day Miguel,

In the example you provide, there would be real energy flowing and
it would be clearly shown by
P(t)=V(t)*I(t)
P(t) will be negative because the energy is flowing in the reverse
direction.

Computing Pf and Pr would reveal
Pf(t)=0
Pr(t)=-P(t)

So Pf(t)-Pr(t) = P(t) as it must.

I see no conflict with anything that I have written previously.

There are many examples where one can observe energy flow in a
reflected wave.

It just takes one counter-example to demonstrate that this is not
always
the case and that one should not assign *too* much reality to such
waves.

What this neans is that when someone asks "what happesn to reflected
energy?", the first question you have to answer is "Is this a
situation
where the computed reflected power represents something real?"
because
if it does not, the original question is moot.

....Keith