On Apr 22, 1:12*pm, Cecil Moore wrote:
Cecil Moore wrote:
Keith Dysart wrote:
What I have said is that an ideal voltage source removes energy
from a circuit ...

Sorry, you specifically said that an ideal voltage source
"absorbs" energy, i.e. irreversibly converts energy to
another form, the most common form of which is heat.

In case you have forgotten :-), here is what you posted
over the past few days:

With your difficulty using the word 'absorb' to represent the
abstract concept of removing energy without knowing where it
goes, for a better understanding please re-read these passages
substituting 'remove' for 'absorb'.

When it is sinking current, it is *absorbing* energy.

You will find that for some of the time
energy is being *absorbed* by the source.

But we do know that when the sign of Ps(t) is
negative, the source is *absorbing* energy from
the system,

When current flows into a voltage source, the
voltage source is *absorbing* energy.

And how do you know the ideal source does not dispose
of the energy it receives by getting warm?

This certainly implies that you consider the dissipation
of "absorbed" energy to be a distinct probability.

It certainly is one of the many possible things that might
happen to the energy that is removed. As I wrote previously,
"In practice, devices which are designed to approximate
ideal voltage sources do simply dissipate the energy they
remove from the circuit."

Still, since we do not *know* what happens to the energy removed
by an ideal voltage source, we can make no assumptions.

The source provides or *absorbs* energy.

When 1.5 amps is flowing into the positive terminal,
the ideal voltage source is *absorbing* 15 joules per
second from the circuit.

The ideal voltage source on the right is *absorbing*
5 joules/second from the circuit.

An ideal source provides or *absorbs* energy to
satisfy its basic function which is to hold the
voltage across its terminals at the desired value.

When it is providing energy we do not know where
this energy comes from and when it is *absorbing*
energy we do not know where this energy goes.

But was this because you have learned that you were
in error and now better understand the behaviour of
sources when they are *absorbing* energy?

The ideal voltage source on the right, after the
circuits settle, will be absorbing 50 joules/s
in both cases.

Where does the energy being *absorbed* by these ideal
voltage sources go?

The element *absorbing* energy is an ideal voltage
source, not a resistor.

Despite your protests to the contrary, ideal voltage
sources can, and do, *absorb* energy.

You know, Keith, if you were just ethical enough to
answer my questions, I wouldn't have to treat you
this way.

Perhaps. But I doubt that it would actually alter your
behaviours.

...Keith