what happens to reflected energy ?
On Jul 5, 9:07*am, Cecil Moore wrote:
On Jul 4, 8:24*pm, Keith Dysart wrote:
From Wikipedia, I have just learned that the concept I am
attempting to describe is known as a "Continuity equation".
In all your previous equations, you have presented only the first term
and completely ignored the second (delta-dot-v) term of the equation
which is required for balance. When you add the proper term, i.e. you
track and account for all of the energy, your energy equation will
balance - as I told you days ago.
So you now are in agreement that flows must balance if charge (or
energy)
is to be conserved. Excellent.
So how do you characterize a slow square wave? Say one that is 0V for
one year, then 10V for a year, then 0, then...
The same way I characterize, "How many angels can dance on the head of
a pin?" The length of time makes absolutely no difference to the
concept involved. The above conditions do not match the DC steady-
state conditions of your earlier example.
With an infinitely long transmission line excited by a step function,
is there an EM wave propagating down the line?
Yes, there is an EM wave at the leading edge.
For greater certainty, I paraphrase: "Only the leading edge has an EM
wave".
What is follows just after the leading edge since it is not an EM
wave?
What is it? What do you call it?
Now back to the square wave with a two year period...
After the rising edge goes by, which I assume you will still call an
EM wave, what follows until the falling edge occurs a year later?
Is it an EM wave?
If so, how is it different than what follows the rising edge of the
step wave? They both look like DC for a year.
If not, why is it not an EM wave?
....Keith
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