studiot,

Your program specified 0 to 2pi so each 'phase' value appears only once and your waveforms are single valued.

It's the way a polar plot works. Look at how the polar plot and rectangular plot track for the voltage. At 0 deg phase, the magnitude is 42. At 90 deg the value returns to 42. At 180 deg the value is again 42. At 270 deg the magnitude is -142, so the value is plotted on the positive y-axis. This makes it appear like a double value function.

Look at a polar curve like the bifolium. http://en.wikipedia.org/wiki/Bifolium . That curve retraces itself from 180 deg to 360 deg. When it is rectangularly plotted, all the values from 0 deg to 180 deg are positive, and from 180 to 360 are negative.

Ratch

 

It doesn't. Who said it did?

You did, in posts #73 and #75. But let's try again: How does re-naming "time" as "angle" or "yellow" or "Studiot" keep it from being time? Young Ms Capulet's comment on flora comes to mind.

 

thingmaker3,

You did, in posts #73 and #75. But let's try again: How does re-naming "time" as "angle" or "yellow" or "Studiot" keep it from being time?

You are mistaken. I never said I was renaming time. I was talking about expressing the the magnitude is of the voltage with respect to some variable other than time, and discussed doing that. Time is time, and it does not change by renaming it, which I did not do.

Young Ms Capulet's comment on flora comes to mind

Who is Ms. Capulet?

Ratch

 

I was talking about expressing the the magnitude is of the voltage with respect to some variable other than time, and discussed doing that.

How do you divorce the "other variable" from time?

Time is time, and it does not change by renaming it,

Nor will it. Nor has it. Ditto for roses (see below.)

which I did not do.

Not if I had any say in the matter, you didn't!

Who is Ms. Capulet?

You know... the chick who caught the eye of the Montague boy.. here.

'Tis but thy name that is my enemy.
Thou art thyself, though not a Montague.
What's Montague? It is nor hand, nor foot,
Nor arm, nor face. O, be some other name
Belonging to a man.
What's in a name? That which we call a rose
By any other word would smell as sweet.
So Romeo would, were he not Romeo called,
Retain that dear perfection which he owes
Without that title. Romeo, doff thy name;
And for thy name which is no part of thee,
Take all myself.

She's not a vector, but a phasor is.

 

thingmaker3,

How do you divorce the "other variable" from time?

Already asked, already answered.

Nor will it. Nor has it. Ditto for roses (see below.)

I am glad we agree on that.

Not if I had any say in the matter, you didn't!

Did you? Did I?

You know... the chick who caught the eye of the Montague boy.. here.

Well I don't know, not do I care. Billy Shakespeare is one of the most over hyped writer of the English language. Most people can't stand to read him due to his flowerly language. I am willfully ignorant of his works, and most of my knowledge of his works come from hearsay. Public television ran a program a few years back which avered that Billy did not really write those works. Instead it was done by some earl nobleman, who the powers that were at the time. changed the records to indicate that Billy, a commoner, really wrote them. They could not even find a verified signature of the bard, and very little of his personal life. Shakespeare and science don't mix too well, in my opinion at least.

She's not a vector, but a phasor is.

Vectors don't have to rotate, phasors do. As you said before, calling something that it isn't does not make it what you want it to be.

Ratch

 

Public television ran a program a few years back which avered that Billy did not really write those works. Instead it was done by some earl nobleman, who the powers that were at the time. changed the records to indicate that Billy, a commoner, really wrote them. They could not even find a verified signature of the bard, and very little of his personal life.

Your TV program refers to "Sir Francis Bacon."

Shakespeare and science don't mix too well, in my opinion at least.[/qutoe]This thread has as much (or more) to do with language as with science. Besides, you've already agreed that changing a name does not change the named. Twice.

Vectors don't have to rotate,[/qutoe]Well, of course they don't. But do they stop being vectors if they do rotate? Does an insect stop being an insect if it has broad colorful wings? (Ref. post #48)

As you said before, calling something that it isn't does not make it what you want it to be.

And calling something that is does not make it what you don't want it to be. Look up the "tu quoque" fallacy.

 

thingmaker3,

Your TV program refers to "Sir Francis Bacon."

No, definitely not. I remember them analyizing the language. It was Billy they were talking about all right. http://www.pbs.org/wgbh/pages/frontline/shakespeare/debates/ogburnarticle.html

Shakespeare and science don't mix too well, in my opinion at least.[/qutoe]This thread has as much (or more) to do with language as with science. Besides, you've already agreed that changing a name does not change the named. Twice.

Yes, and Billy is no help at all. Yes, I said it twice or more already. And the point is?

Vectors don't have to rotate,[/qutoe]Well, of course they don't. But do they stop being vectors if they do rotate? Does an insect stop being an insect if it has broad colorful wings? (Ref. post #48)

My contention is that a phasor does not exist unless it rotates. It was never a vector in the first place. Voltage is not a vector. The sinusoidal variation of its magnitude is not a vector either.

And calling something that is does not make it what you don't want it to be. Look up the "tu quoque" fallacy.

That act by itself would be as you say, but I gave reasons for what I called a phasor. And the reasons do not rely on naming something different.

Ratch

 

I must say, you are an unusual group of people to contemplate such a simple question in these complex ways. It is so clear that Phasors are vectors. How can you spend more than one minute thinking about it?

A phasor is a complex number that has a magnitude and direction in an abstract space (i.e. complex plane). Phasors are defined to be vectors from the onset and meet all the properties that vectors require, by definition. This specialized vector is useful in that its magnitude and direction can correlate with the magnitude and phase of steady state sinusoidal signals in linear systems.

The usual definition of a phasor requires divorcing the time dependence from the vector, since it is just a fixed constant rotation rate (wt) that provides no useful information. This is exactly the same as in a Fourier transform, as the two are intimately related. However, even if one retains the time dependence in the phasor definition, the phasor is still a vector, but is now a time dependent one.

That's all I'll say about it, as I don't want to get drawn into all your nonsense. Don't you guys have better things to do?

 

It's the way a polar plot works.

Thank you Ratch I apologise I should have appreciated that. Hover I was a bit confused by placing cartesian axes against a polar plot. My Zip file show how I would have expected a polar plot to work. It has the same shape as yours, but different grid lines.

Unfortunately there is no way this can be called a phasor diagram. I distinctly remember asking for one as I suggested it is impossible to draw a single phasor diagram when there are several different frequencies present and you suggest you could do this.

AliceT
Welcome to AAC.
Do you wear a black hat or a white hat?

I can't see whay all the fuss about divorcing time from something is all about.

If A is related to B
and B is related to C
then A is related to C by the composite relation

So the axis label is irrelevant and only a simple transformation away from anything you want it to be. A phase difference can also be regarded as a time difference or even a length difference. This last is actually the basis of the Tellurometer distance measurement system.

 

Yes, I said it twice or more already. And the point is?

The point is "phasors are vectors." Havn't you been paying attention?

My contention is that a phasor does not exist unless it rotates.

Nothing exists. I thought we'd been over this already.

It was never a vector in the first place.

Sure it was.

Voltage is not a vector.

It's not a phasor either. We can, however, represent it with a vector - specifically with a phasor.

The sinusoidal variation of its magnitude is not a vector either.

And niether Sir Francis Bacon nor William Shakespear are the words we use to describe them. They are persons, at least one of which was real.

That act by itself would be as you say, but I gave reasons for what I called a phasor.

You did not, however, demonstrate a lack of subcategorical relationship, as required by your assertion. Studiot, Alice, and I have provided plenty of evidence of said relationship.

============

I must say, you are an unusual group of people to contemplate such a simple question in these complex ways.

Hi Steveb! Welcome back!

It is so clear that Phasors are vectors.

Not to Ratch it isn't.

How can you spend more than one minute thinking about it?

Well, Ratch does it by re-defining "time" as "not time." The rest of us play with Ratch because he's entertaining on a certain level. Every once in a while we even learn something from each other.

=============

I can't see whay all the fuss about divorcing time from something is all about.

If A is related to B
and B is related to C
then A is related to C by the composite relation

I concur. Time is measured in degrees or radians or seconds.

 

AlliceT,

I must say, you are an unusual group of people to contemplate such a simple question in these complex ways. It is so clear that Phasors are vectors. How can you spend more than one minute thinking about it?

We all know to manipulate phasors to get answers. We argue on concepts.

Phasors are defined to be vectors from the onset and meet all the properties that vectors require, by definition.

I think not. As studiot pointed out in posts #1 & #2 in this thread, phasors live in vector space. That does not mean they are vectors in the engineering sense, however. I say they possess different properties than vectors and lack some properties. They can be divided by another phasor, and raised to a power. Vectors cannot. Phasors do not have a box product.

However, even if one retains the time dependence in the phasor definition, the phasor is still a vector, but is now a time dependent one.

No, if there evidence of time, it is no longer a phasor. See the first sentence of http://en.wikipedia.org/wiki/Phasor_(electronics) .

Ratch

 

studiot,

Unfortunately there is no way this can be called a phasor diagram. I distinctly remember asking for one as I suggested it is impossible to draw a single phasor diagram when there are several different frequencies present and you suggest you could do this.

Why not? It charts magnitude vs. angle of the composite wave.

So the axis label is irrelevant and only a simple transformation away from anything you want it to be.

If it is not time-invariant, it is not a phasor.

Ratch

 

However, even if one retains the time dependence in the phasor definition, the phasor is still a vector, but is now a time dependent one.

No, if there evidence of time, it is no longer a phasor. See the first sentence of http://en.wikipedia.org/wiki/Phasor_(electronics) .

Ratch

You are clearly a manipulative person. You deliberately misquoted me. You saw that I said that the definition of a Phasor removes the time component, but that if you wanted to keep the time dependence the vector qualities would remain. However, you selectively removed that part.

Who do you think you are fooling? Why does anyone even talk to you? I certainly never will again.

You are very transparent. You provoke people just for fun. It's clear to me that you do not even believe your stupid arguments.

By the way, your link leads nowhere, which I find very appropriate, as it resembles your line of reasoning.

EDIT: OK, I figured out how to get to the page you intended. The first line says that the Phasor is a vector. And, it says that the Amplitude, Frequency and Phase are time invariant, not the Phase Vector itself.

 

thingmaker3,

The point is "phasors are vectors." Havn't you been paying attention?

You are confused. The argument is about "phasors are vectors.". What is the point you are trying to make in regard to my stating twice that giving something a name does not make it so?

Nothing exists. I thought we'd been over this already.

You proposed that silliness, I never agreed to that preposterous proposition.

It's not a phasor either. We can, however, represent it with a vector - specifically with a phasor.

It is a phasor when the magnitude changes with respect to phase.

And niether Sir Francis Bacon nor William Shakespear are the words we use to describe them. They are persons, at least one of which was real.

So why are you dragging their name into this discussion. Did they know anything about phasors?

You did not, however, demonstrate a lack of subcategorical relationship, as required by your assertion. Studiot, Alice, and I have provided plenty of evidence of said relationship.

That's because I don't believe they are "subcategorical". Although they have vector space properties, they are different enough to be in a class by themselves.

I concur. Time is measured in degrees or radians or seconds.

If I said I would meet you in a couple of radians, would you know when to meet me?

Ratch

 

AliceT,

You are clearly a manipulative person. You deliberately misquoted me. You saw that I said that the definition of a Phasor removes the time component, but that if you wanted to keep the time dependence the vector qualities would remain. However, you selectively removed that part.

I did not misquote you. I cut and pasted your exact words. However, I think I misunderstood you. I believe I now know what you are averring, but I still do not agree with you.

Who do you think you are fooling? Why does anyone even talk to you? I certainly never will again.

Because I make some cogent points sometimes. It is your privilege to post or not post according to your wishes.

You are very transparent. You provoke people just for fun. It's clear to me that you do not even believe your stupid arguments.

I think clear is a better word. Well, I do believe what I say. Ask me about "current flow" and "Ohm's law sometime.

By the way, your link leads nowhere, which I find very appropriate, as it resembles your line of reasoning.

EDIT: OK, I figured out how to get to the page you intended. The first line says that the Phasor is a vector. And, it says that the Amplitude, Frequency and Phase are time invariant, not the Phase Vector itself.

Hmm. The link I posted does not go to the site where I wanted to go either. You must be at a still different site, because the site I was at does not say that a phasor (notice the lower capitalization) is a vector. It is not hard to find many sites and textbooks that do equate phasors to vectors. But within this thread I found a textbook that does not do so, and infers that there is a difference. Search this thread for Kosow if you are interested.

Ratch

 

As studiot pointed out in posts #1 & #2 in this thread, phasors live in vector space. That does not mean they are vectors in the engineering sense, however.

Anything that lives in a vector space is a vector by definition. All vectors are alike in that there is some sort of addition operation in that space that obeys a small number of axioms, and another sort of multiplication between scalars and the vectors that likewise obeys a few axioms.

Beyond those basic properties that all vectors satisfy, there can be a wide variation in vectors in one vector space and vectors in another vector space. Ratch, it seems to me that your notion of vectors extends to three dimensions and no further. On the contrary, a vector space can consist of matrices, including ones that aren't square, functions, finite or infinite sequences of numbers, real or complex, not to mention pairs, triples, quadruples, n-tuples or real or complex numbers.

I say they possess different properties than vectors and lack some properties.

As noted above, that doesn't detract from them (phasors) being vectors. As long as they follow the basic axioms of vector-ness, they are vectors. The fact that they have additional properties is just icing on the cake.

They can be divided by another phasor, and raised to a power. Vectors cannot. Phasors do not have a box product.

Yes, and, for example, matrices (of appropriate sizes) multiplied, raised to powers, and exponentiated (used as the exponent on, say, e). The fact that phasors don't have a box product -- so what. The box product is not an essential property of vectors -- most vectors don't have a box product, nor in fact do most of them have even a cross product.

To put this idea across in a different way, we participants in this forum are all mammals. In my house live two dogs who are also mammals. Several of my neighbors have cats, and the cats, too are mammals. Now all of us, people, dogs, and cats have certain properties (like being born alive, being warm-blooded, being fed milk by our mothers, and so on) that we as mammals share. Beyond these properties there are distinguishing differences, so that a dog is not a cat, a cat is not a person, and so on. But all are mammals.

It works the same way with vectors and the various subcategories of things that I have described that share the properties of vectors. In fundamental ways they are alike, but they don't have to be exactly the same.

No, if there evidence of time, it is no longer a phasor. See the first sentence of http://en.wikipedia.org/wiki/Phasor_(electronics) .

Ratch

 

What is the point you are trying to make in regard to my stating twice that giving something a name does not make it so?

I apologise for my ambiguity. My point is that phasors are vectors.

You proposed that silliness, I never agreed to that preposterous proposition.

No one ever said you agreed to it. I said we've been over it. It is a valid philosophical position, however. But then you don't take interest in philosophy.

It is a phasor when the magnitude changes with respect to phase.

No. It is voltage. It is simply representedwith a type of vector called a phasor. But then you don't take interest in philosophy.

So why are you dragging their name into this discussion. Did they know anything about phasors?

They knew about WORDS. But then you don't take interest in words.

That's because I don't believe they are "subcategorical".

Obviously.

Although they have vector space properties, they are different enough to be in a class by themselves.

Now all you have to do is convince everyone else of what you believe.

If I said I would meet you in a couple of radians, would you know when to meet me?

If you specified the frequency, then you betcha! And YOU are buying the first round!

 

thingmaker3,Mark44,studiot,

I have two books on linear algebra, and neither of them mention that vectors can be exponentiated, or divided. Also they make no mention of phasors. Only when I read about phasors in engineering literature do I see phasors and those operations mentioned. Could it be that phasors are a superset of vectors?

Anyway, I am willing to concede that vectors and phasors are closely related because they both share vector space with respect to a small set of axioms. That is what mathematicans are happy with. Engineers seem to want a little more specificity in defining what the vector space is.

So, I think we all know how each other thinks about this. We also know that all of us are proficient in solving vector/phasor problems. Since we all had our say, I don't think it is necessary to continue this discussion.

Ratch

 

Hmm. The link I posted does not go to the site where I wanted to go either. You must be at a still different site, because the site I was at does not say that a phasor (notice the lower capitalization) is a vector. It is not hard to find many sites and textbooks that do equate phasors to vectors. But within this thread I found a textbook that does not do so, and infers that there is a difference. Search this thread for Kosow if you are interested.

Ratch

To anyone who wants to see evidence of an obvious Ratch lie:

Go to Ratch's previously quoted link, but add the parenthesis at the end....

here I'll do it for you, just cut and paste the following text into your browser, but go back and check his post so you see I don't lie.

http://en.wikipedia.org/wiki/Phasor_(electronics)

So the first line says the following:

In physics and engineering, a phase vector ("phasor") is a representation of a sinewave whose amplitude (A), phase (θ), and frequency (ω) are time-invariant.

His own quoted reference says that a Phasor is a vector, but now he twists it around and tries to slip away. Always twisting and slipping this guy. I say he does it deliberately for fun, but he says he seriously believes his claims. Well, you decide. Is he malicious, or just deranged?

 

thingmaker3,Mark44,studiot,

I have two books on linear algebra, and neither of them mention that vectors can be exponentiated, or divided.

That's correct. The only required operations for vector space membership are an operation to add them and an operation to multiply them by a scalar. As long as these basic operations are included, the members of different kinds of vector spaces are free to have additional operations that are not necessarily shared by members of other kinds of vector spaces.

Also they make no mention of phasors. Only when I read about phasors in engineering literature do I see phasors and those operations mentioned. Could it be that phasors are a superset of vectors?

YES!!! Several of us have been trying valiantly to make exactly that point. Matrices, phasors, and the mathematical structures mentioned earlier are supersets of vectors.