#### nicholaaaas

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PF= Cos(Tan^-1(VARS/True Power))

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PF= Cos(Tan^-1(VARS/True Power))

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You have certainly straightened me out about this thread.

I agree... So trying to convince me of something differnet than what I observed yet do not adhere to is a waste of your time... IMO. ...

Using the current english definition of "instantaneous", this statement is wrong. Please note that I am certainly not trying to convinince you of this fact.... If I tell you I had a reactive load for which I measured 56V and 3A at one instant, can you tell me the real and reactive power portions of the current? No you cannot. ... .

Yor're right. In fact, for this thread I vote for pig latin... I didn't see any guidelines that said I had to restrict my usage of the english language...

Is this a pun on "Dirk Gently's Holistic Detective Agency". If it is, it's a good one....I embody knowledge as a whole, and use it as such. ...

For this I am horrible apologetic. In my defence, I can only say that adhering to the known body of the laws of God and physics that have been built upon for the last 350 years, would never have occured to me as asking you to lessen yourself. I would never want you to do that.... I shall not lessen myself for the likes of others. ...

Iyay inkthay Iyay dooday.:grin:...Sorry if you can't understand...

later

cf

What about it is wrong????......

Using the current english definition of "instantaneous", this statement is wrong. Please note that I am certainly not trying to convinince you of this fact.Smart $ said:... If I tell you I had a reactive load for which I measured 56V and 3A at one instant, can you tell me the real and reactive power portions of the current? No you cannot. ... .

Merriam-Webster Collegiate? Dictionary

in?stan?ta?neous

1 : done, occurring, or acting without any perceptible duration of time <death was instantaneous>

2 : done without any delay being purposely introduced <took instantaneous action to correct the abuse>

3 :occurring or present at a particular instant<instantaneous velocity>

Not a pun at all... it's interesting though that you found it entertaining.Is this a pun on "Dirk Gently's Holistic Detective Agency". If it is, it's a good one.

I do believe you would not do it... knowingly. But sometimes people's eyes have to be opened for them. And your defense is pretty weak considering my offense has essentially the same backgroundFor this I am horrible apologetic. In my defence, I can only say that adhering to the known body of the laws of God and physics that have been built upon for the last 350 years, would never have occured to me as asking you to lessen yourself. I would never want you to do that.

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What about it is wrong????...

I'll be staying out of this unless it goes technical.[B said:Smart $][/b]

... So trying to convince me of something differnet than what I observed yet do not adhere to is a waste of your time... IMO....

cf

It isn't going anywhere. You made the assertion. You bugged out. Where do think its going to go? Perhaps you just prefer that it go awayI'll be staying out of this unless it goes technical.

cf

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gar, Smart, gunn, and others ,100415-1956 EST

Make the phase angle 0, then the equation reduces to 1 + cos 2t. This wrong.

.

please make clear for me.

p = P + Pcos2wt Is this wrong or Right

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No I'm still here. I don't know where the thread will go. I don't have a preference.It isn't going anywhere. You made the assertion. You bugged out. Where do think its going to go? Perhaps you just prefer that it go away

Why is this wrong? Well, it is a trick question - I can't tell you because there isn't any. All of the necessary discussion detailing why this is true has already been posted. Repeating won't help. So, I am following your lead..... If I tell you I had a reactive load for which I measured 56V and 3A at one instant, can you tell me the real and reactive power portions of the current? No you cannot. .

....So trying to convince me of something differnet than what I observed yet do not adhere to is a waste of your time...

- Location
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Ham:

See

http://www.karlscalculus.org/trig_id.html

Go to equations 7.1b-10a and 10b

In post 155 I clearly indicated what sin^2 t was.

In post 179 you provided a plot of instantaneous power to a resistor without a specified relation to the voltage, and your assumption was for a cosine voltage curve without my knowing that. I had to assume you were referring to a sine wave because that was what I had defined in post 155, and the post to which you were questioning.

.

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Gar:

Ham:

See

http://www.karlscalculus.org/trig_id.html

Go to equations 7.1b-10a and 10b

In post 155 I clearly indicated what sin^2 t was.

In post 179 you provided a plot of instantaneous power to a resistor without a specified relation to the voltage, and your assumption was for a cosine voltage curve without my knowing that. I had to assume you were referring to a sine wave because that was what I had defined in post 155, and the post to which you were questioning.

.

Thanks for link and I have no problem with trigometery equation and I am just to know from you

p = p + pcos2wt is right or wrong that is all.

- Location
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100417-0941 EST

Ham:

It is wrong for a sine wave and correct for a cosine wave.

.

Ham:

It is wrong for a sine wave and correct for a cosine wave.

.

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ok thanks. I thought you are saying for ploting the graph sin^2 is correct and con^2 is wrong.100417-0941 EST

Ham:

It is wrong for a sine wave and correct for a cosine wave.

.

another thing I have seen that you are prefering sin^2 for ploting than cos^2 and most of books provide cos^2

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Ham -Gar:

Thanks for link and I have no problem with trigometery equation and I am just to know from you

p = p + pcos2wt is right or wrong that is all.

I'm not jumping in. I just have a question to help me follow along.

Can I rewrite p = p + pcos2wt as:

p(t) = VI + VIcos2wt or:

p(t) = VI (1 + cos2wt)

If I can, that will help me understand what your are saying. If not, then I am still lost - but that's okay, I'll catch up eventually.

cf

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Ham:

The reason I prefer sine waves is that I grew up with them, and it is virtually impossible to synchronize on the peak of a waveform on an oscilloscope. Too much amplitude variation and dv/dt is small.

I have no idea what current books do when discussing sinusoidal waveforms. In general the books I have discuss sine waves as the reference.

Except for special reasons, on most arbitrary waveforms I synchronize on a zero crossing. But for TTL logic it is usually about 2 V. Zero crossing sync for sinusoidal waveforms means I am looking at a sine wave.

.

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Ok wait please and there is a confusion for me too. I know you, smart and gar are more experience than me. But I want to make it clear for me.Ham -

I'm not jumping in. I just have a question to help me follow along.

Can I rewrite p = p + pcos2wt as:

p(t) = VI + VIcos2wt or:

p(t) = VI (1 + cos2wt)

If I can, that will help me understand what your are saying. If not, then I am still lost - but that's okay, I'll catch up eventually.

cf

Trying to catch up here...gar, Smart, gunn, and others ,

please make clear for me.

p = P + Pcos2wt Is this wrong or Right

I followed your "proof" in post # 240.

p = P + Pcos2wt is correct when θv=θi, or pf=1.

Otherwise, the third term in your proof does not cancel out (i.e. where θv<>θi or pf<1).

p = P + Pcos2wt - Vm*Im*sin(0v - 0i)sin2wt/2

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sorry for late answer you.Ham -

I'm not jumping in. I just have a question to help me follow along.

Can I rewrite p = p + pcos2wt as:

p(t) = VI + VIcos2wt or:

p(t) = VI (1 + cos2wt)

If I can, that will help me understand what your are saying. If not, then I am still lost - but that's okay, I'll catch up eventually.

cf

yes, ofcourse you can incase you have pf = 1.

Ummm... forgot to mention your "P" is not an accurate representation of P_real. You reduced your eq. 8 by P=Vm*Im cos(0v-0i)/2. The waveform of P_real is Vm*cos(wt)*Im*cos(0v-0i)Trying to catch up here...

I followed your "proof" in post # 240.

p = P + Pcos2wt is correct when θv=θi, or pf=1.

Otherwise, the third term in your proof does not cancel out (i.e. where θv<>θi or pf<1).

p = P + Pcos2wt - Vm*Im*sin(0v - 0i)sin2wt/2

Unless you are computer language scripting, rewriting the equation with lower case p on both sides of the equation as cf did does not make any mathematical sense unless for all instances of t, cos2wt=0sorry for late answer you.Ham -

I'm not jumping in. I just have a question to help me follow along.

Can I rewrite p = p + pcos2wt as:

p(t) = VI + VIcos2wt or:

p(t) = VI (1 + cos2wt)

If I can, that will help me understand what your are saying. If not, then I am still lost - but that's okay, I'll catch up eventually.

cf

yes, ofcourse you can incase you have pf = 1.

- Location
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I'm not jumping in. I just have a question to help me follow along.

Can I rewrite p = p + pcos2wt as:

p(t) = VI + VIcos2wt or:

p(t) = VI (1 + cos2wt)

If I can, that will help me understand what your are saying. If not, then I am still lost - but that's okay, I'll catch up eventually.

cf

My only concern, p = p + pcos2wt should be ploted by consin not by sine. Because

1- According to Electric Circuits 7th Edition Nilsson-Riedel 2004 book it says.

We are operating in the sinusoidal steady state, so we may choose any convenient reference for zero time. Engineers concerned with operating systems involving the transfer of large blocks of power have found that a zero time corresponding to the instant when the current is passing through a positive maximum is convenient.

2- According to Transforms and Applications Handbook, Third Edition by Alexander D. Poularikas.page-51

p = cos(0i-0v) = P/S

"is called the power factor. The power factor may be regarded as a normalized correlation coefficient of the voltage and current signals while sin(0i - 0v) = SQR(1 - sqr(p)) may be called the anticorrelation of coefficient.

Now I need your help and I might be wrong but I want to clear my self thanks

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Smart$ I have to go out and will reply you later.Unless you are computer language scripting, rewriting the equation with lower case p on both sides of the equation as cf did does not make any mathematical sense unless for all instances of t, cos2wt=0

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