Re: Intensity and what else affects a single ligth beam's temperature?

"Sue..." <suzysewnshow@xxxxxxxxxxxx> wrote in
news:1186035842.775573.83290@xxxxxxxxxxxxxxxxxxxxxxxxxxxx:

On Aug 1, 10:53 pm, bz <bz+...@xxxxxxxxxxxxxxxxxxxx> wrote:
"Sue..." <suzysewns...@xxxxxxxxxxxx> wrote in
news:1185994988.729472.276220 @q3g2000prf.googlegroups.com:

On Jul 30, 9:03 am, bz <bz+...@xxxxxxxxxxxxxxxxxxxx> wrote:


bz's experitment:
"It is quite possible to measure the voltage and current, instant by
instant, multiply them together and integrate,
getting the average power."


f = 50 or 60 Hz
C = 22uf
R = 0.01 ohms

Anxious to see how your results differ.
http://en.wikipedia.org/wiki/Power_factor

What makes you think my results will differ?

From p49,50 Basic Electronics for Scientists, James J. Brophy IIT
Research Institute, McGraw-Hill, 1966
[quote]
Power Factor

Suppose that the current and voltage in some portion of a circuit are
given by
i = Ip sin(wt)
v = Vp sin(wt + phi)
[here i is current, Ip is peak current w is omega, the frequency
factor, t is time
v is voltage, Vp is peak voltage, phi is the phase difference
between
i and v, if any]

No... that is not what you propsed above.
phi is imaginary time.

What is imaginary about Phi? Assertion does not make it so. Show me exactly
how an angle is imaginary.

You were going show we don't need imaginary time.
But you used imaginary time in the second equation.

Phi is no more imaginary time than omega is. It just represent the phase
difference between the voltage and the current.


You have said:
"Note, this is a matter of convenience, NOT a
matter of the reactance actually being imaginary!"

Show me how Phi is imaginary.


So take phi out of the equation and prove your
statement... or withdraw it.

The dollars in your bank account as calculated by your bank is out of phase
with the cheques you have issued and deposits you have made. That does NOT
make those cheques and deposits imaginary. They are quite real. Even if a
cheque gets lost in the mail, it is real.

....
The instantaneous power is then
p = vi = VpIp sin(wt) sin(wt+ phi)

.....

Now, will you believe me when I tell you that the imaginary axis is
just used for convenience? The voltage and current are real?

No... I won't believe it. You used imaginary time in
your second equation.


There is nothing imaginary about an angle.

The north pole and the magnetic north pole differ by an angle. There is
nothing imaginary about that angle.

The voltage peak and the current peak through a reactive device differ by
an angle. There is nothing imaginary about that angle.

The formula I gave allow you to calculate the voltage at any instant in
time during the cycle.
The formula I gave allow you to calculate the current at any instant in
time during the cycle.
There is nothing imaginary about that voltage nor that current.

I could have just as easily taken my oscilloscope and measured that angle.
An oscilloscope does not measure imaginary things, only physical things.

I showed you that imaginary numbers were not required for the calculations.

Show me that phi is a special letter reserved only for imaginary angles.
Show me where imaginary numbers are used by my oscilloscope.

Show me where imaginary numbers MUST be used to convert between rectangular
coordinates and polar coordinates, because that is what you appear to be
claiming.

If you don't believe me, still, perhaps you will take this quote from
the book cited above:
[quote from page 85, complex impedance]
It is convenient to represent the two elements of reactance, the
magnitude and phase angle, in such a way that the results of combining
several resistances and reactances can be determined easily. This is
done by representing reactance as a complex number. The real part of
the complex number is associated with the resistance while the
imaginary part stands for reactance.
[unquote]

Note, this is a matter of convenience, NOT a matter of the reactance
actually being imaginary!

You have been laboring under a misconception.

You have been laboring under a similar misconception when thinking
about time in Minkowski space, it is a matter of convenience, not a
matter of time being imaginary!

I realize that it is sometimes difficult to give up ones illusions. But a
scientist is always ready to reexamine ones cherished beliefs and abandon
them when they prove to be at odds with reality. Can you let go of the idea
that an angle is imaginary or show me why it must be?



--
bz

please pardon my infinite ignorance, the set-of-things-I-do-not-know is an
infinite set.

bz+spr@xxxxxxxxxxxxxxxxxxxx remove ch100-5 to avoid spam trap
.

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