I respectfully disagree. I am a Christian, and one of my good friends is a self described athiest. We've had a few (read less than four in ten years) civil discussions on the topic of religion, and he usually finds a civil means of escaping from the conversation...he's always careful to avoid harsh and offensive generalisations of those with whom he disagrees. I also strive to avoid making such blanket statements, as I know it to be true that you can disagree with someone without hating them.
People who harm (verbally, physically, etc) or intend to harm those with whom they disagree do a great disservice to their own personal beliefs. Belittling someone else because of their beliefs is "poor sportsmanship"....so to speak...
You're right. The numbers don't add up. I don't see any way that would allow them to NOT be breaking conservation of energy...at least not without doing something underhanded like hidden batteries or somehow draining off the stored magnetism of the magnets.
No prob on the school thing. Your joke was funny, not offensive.
When you are using inductive devices, such as an electrical motor, the device does not simply present a real resistive load to the network, but rather a complex load, mainly inductive. As can be demonstrated by just about any circuit theory text, (in AC, of course) the voltage and current through a complex load will be out of phase with each other.
Zcap = 1/(j*C*radial freq)
Zind = j*L*radial freq
where j = sqrt(-1)
So I've been found out... I hated my power classes. Ergo, I've chosen another avenue in EE, as my name belies.
As you state, V and I are vectors in the complex plane. Obviously, the maximum of the vector multiplication (assuming dot product) exists when the two vectors lie along the same line. If the vectors are not linearly dependent, then you get the Preal and Pimaginary, as you state.
Even with phasor/vector considerations included, the measured values from the article don't mention the relative phases of the V and I.
Assumption alert: I would assume that their measured V's and I's are RMS, as opposed to peak values.
Would you agree, (insert name of EE specialising in power)?
Not necessarily. Distance scales by the inverse of the atmospheric absorption. Of course there are many, many other factors involved: EM noise from the environment, RF noise from pre-existing transmitters using this frequency range, power of the transmitter, effective area of the transmitter (or receiver), modulation scheme (how data is modulated onto the RF carrier--for example, AM, FM, PM, digitization then FM, etc), and a whole host of other issues.
(for me, when I get my masters).
This is great news, as it'll allow me to use my skills with HFSS and ADS to more easily get a job engineering microwave and millimeterwave monolithic and integrated circuitry!
Yay!
Yes, but in AC, the total power is equal to the product of the RMS values of the current and voltage..... P=I*V.
When the PF is less than one, that just means that the current and voltage are out of phase with each other, this does not reduce the RMS values of the current and voltage, and thus the total power mentioned here is STILL an impossiblity.
Of course, five years of Electrcial Engineering could all be a whole bunch of lies, you just never know with these state universities.
I suppose that if he's quickly depleting the stored magnetic field on the permanent magnets that he could get out more electrical power than he put in, but that would only work for a couple rotations of the ol' motor. Aside from that, it don't matter which of the "four fundamental forces of nature" you harness, there ain't no cheating the laws of thermodynamics, even in convenience store cooling fans...
I think for zone plates to be feasible, you need to be a sufficient distance from the source (assuming an isotropic source, radiating spherically---yeah I know it ain't quite that simple), so that the curvature of the spherical wavefronts allows for the 1/2 wavelength transparent/opaque sections to be actually manufacturable. Just how far that is, I suppose depends upon many factors, and quite frankly, I am too lazy to do the math right now.
Oh yeah!! There is nothing in the world like hunkering over that PCB, scorching your fingertips and inhaling the fumes of your lead-based solder...
Wait a sec... lead in lungs = lead in brain = reason why, uh... I, uh... can't think..........
Since a nanometer is 1*10^(-9) meter, it would be rather cumbersome to use a number system that is NOT base 10. I'd hate to have to do unit conversions wherein I'd have to be constantly switching between binary, hex, and decimal...my grades (or work)...would suffer.Severely. Considering that I'm lazy (ahem...efficient) about math.
I was wondering...just what are the current means of focusing X-ray frequency light? In optics the other day, we were looking at zone plates that are used to *focus* a spherical wavefront onto a point (see your copy of Hecht regarding Fresnel diffraction.).
Regarding the numerical aperture relationship to the fidelity of the lithography process... you talkin' 'bout narrow aperture diffraction effects? Such as sinc functions and them Airy patterns? Or am I... offtopic?
I can't quite recall right now, but are "S" and "N" supposed to be in magnitude, or in dB? I think my telecom text may have had an error in the way it stated the formula.
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Ok, that's funny.... But the What Would Jesus Do? Thong is JUST WRONG... Wrong, wrong, wrong.
I respectfully disagree. I am a Christian, and one of my good friends is a self described athiest. We've had a few (read less than four in ten years) civil discussions on the topic of religion, and he usually finds a civil means of escaping from the conversation...he's always careful to avoid harsh and offensive generalisations of those with whom he disagrees. I also strive to avoid making such blanket statements, as I know it to be true that you can disagree with someone without hating them. People who harm (verbally, physically, etc) or intend to harm those with whom they disagree do a great disservice to their own personal beliefs. Belittling someone else because of their beliefs is "poor sportsmanship"....so to speak...
You're right. The numbers don't add up. I don't see any way that would allow them to NOT be breaking conservation of energy...at least not without doing something underhanded like hidden batteries or somehow draining off the stored magnetism of the magnets. No prob on the school thing. Your joke was funny, not offensive.
When you are using inductive devices, such as an electrical motor, the device does not simply present a real resistive load to the network, but rather a complex load, mainly inductive. As can be demonstrated by just about any circuit theory text, (in AC, of course) the voltage and current through a complex load will be out of phase with each other. Zcap = 1/(j*C*radial freq) Zind = j*L*radial freq where j = sqrt(-1)
So I've been found out... I hated my power classes. Ergo, I've chosen another avenue in EE, as my name belies. As you state, V and I are vectors in the complex plane. Obviously, the maximum of the vector multiplication (assuming dot product) exists when the two vectors lie along the same line. If the vectors are not linearly dependent, then you get the Preal and Pimaginary, as you state. Even with phasor/vector considerations included, the measured values from the article don't mention the relative phases of the V and I. Assumption alert: I would assume that their measured V's and I's are RMS, as opposed to peak values. Would you agree, (insert name of EE specialising in power)?
Not necessarily. Distance scales by the inverse of the atmospheric absorption. Of course there are many, many other factors involved: EM noise from the environment, RF noise from pre-existing transmitters using this frequency range, power of the transmitter, effective area of the transmitter (or receiver), modulation scheme (how data is modulated onto the RF carrier--for example, AM, FM, PM, digitization then FM, etc), and a whole host of other issues.
Dang! I knew there was a reason that nobody else around here is studying this stuff!!
(for me, when I get my masters). This is great news, as it'll allow me to use my skills with HFSS and ADS to more easily get a job engineering microwave and millimeterwave monolithic and integrated circuitry! Yay!
Yes, but in AC, the total power is equal to the product of the RMS values of the current and voltage..... P=I*V. When the PF is less than one, that just means that the current and voltage are out of phase with each other, this does not reduce the RMS values of the current and voltage, and thus the total power mentioned here is STILL an impossiblity. Of course, five years of Electrcial Engineering could all be a whole bunch of lies, you just never know with these state universities.
I suppose that if he's quickly depleting the stored magnetic field on the permanent magnets that he could get out more electrical power than he put in, but that would only work for a couple rotations of the ol' motor. Aside from that, it don't matter which of the "four fundamental forces of nature" you harness, there ain't no cheating the laws of thermodynamics, even in convenience store cooling fans...
Skimp? NASA? Never!!! They just don't check what unit systems their engineers use.
I think for zone plates to be feasible, you need to be a sufficient distance from the source (assuming an isotropic source, radiating spherically---yeah I know it ain't quite that simple), so that the curvature of the spherical wavefronts allows for the 1/2 wavelength transparent/opaque sections to be actually manufacturable. Just how far that is, I suppose depends upon many factors, and quite frankly, I am too lazy to do the math right now.
I can finally stop scheduling my appointments by writing on my arm!!
Oh yeah!! There is nothing in the world like hunkering over that PCB, scorching your fingertips and inhaling the fumes of your lead-based solder... Wait a sec... lead in lungs = lead in brain = reason why, uh... I, uh... can't think..........
"...and show who owns this place." I guess that means that I can only rent around here?
Since a nanometer is 1*10^(-9) meter, it would be rather cumbersome to use a number system that is NOT base 10. I'd hate to have to do unit conversions wherein I'd have to be constantly switching between binary, hex, and decimal...my grades (or work)...would suffer.Severely. Considering that I'm lazy (ahem...efficient) about math.
I was wondering...just what are the current means of focusing X-ray frequency light? In optics the other day, we were looking at zone plates that are used to *focus* a spherical wavefront onto a point (see your copy of Hecht regarding Fresnel diffraction.).
Regarding the numerical aperture relationship to the fidelity of the lithography process... you talkin' 'bout narrow aperture diffraction effects? Such as sinc functions and them Airy patterns? Or am I ... offtopic?
I can't quite recall right now, but are "S" and "N" supposed to be in magnitude, or in dB? I think my telecom text may have had an error in the way it stated the formula.