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Author Topic: Magnet Myths and Misconceptions  (Read 611503 times)

Cap-Z-ro

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Re: Magnet Myths and Misconceptions
« Reply #1020 on: January 14, 2015, 05:08:41 AM »
The chicken or the egg...which came first ?


EMJunkie

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Re: Magnet Myths and Misconceptions
« Reply #1021 on: January 14, 2015, 05:14:20 AM »
C'mon Chris, get real please.  Please post your answer.

MileHigh - I have answered your question with more than enough information as to what could be going on! Anyone here can see that!

I suggest you be a little more specific as to what you're looking for if I have not given you what you are looking for. User Defined variables, eg user adjustments to the Variable power supply over time and so on.

If you're trying to be cryptic or avoid the actual test you proposed then you will fail in misery again because you have already defined the test.


tinman

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Re: Magnet Myths and Misconceptions
« Reply #1022 on: January 14, 2015, 05:16:00 AM »
You can call aeronautical SME's "back yard boys" if you like.  In any event, they knew their subject matter backwards and forwards.  They: came up with the concept, proved it on paper (simulations), and then went and built a working proof of concept.  Analysis, simulation, and experiment all correlated.  A lot of smart people were deceived by their own intuition.  That happens.  That's why reliable data always tells the real story.
The same could be done with a boat and flowing river I recon.

MileHigh

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Re: Magnet Myths and Misconceptions
« Reply #1023 on: January 14, 2015, 05:16:18 AM »
There are only two variables.  The voltage is already defined.  Solve for the current.

EMJunkie

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Re: Magnet Myths and Misconceptions
« Reply #1024 on: January 14, 2015, 05:16:27 AM »
The chicken or the egg...which came first ?

@Cap-Z-ro - Feels a bit this way doesn't it! I wonder if there might be a Hedge Hog thrown in there too?

Kind Regards

  Chris

EMJunkie

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Re: Magnet Myths and Misconceptions
« Reply #1025 on: January 14, 2015, 05:20:17 AM »
There are only two variables.  The voltage is already defined.  Solve for the current.

You said no resistance so the only variable is Inductive Reactance which I am not going to give you an answer for!

To many un-knowns to give an answer that could be considered accurate.

Wire size could be 12Awg or it could be 32Awg, to many variables and this will change it all! Size of the coil, Length, W x H or 2piR...

Pirate88179

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Re: Magnet Myths and Misconceptions
« Reply #1026 on: January 14, 2015, 05:22:25 AM »
@Cap-Z-ro - Feels a bit this way doesn't it! I wonder if there might be a Hedge Hog thrown in there too?

Kind Regards

  Chris

MH:

This is Chris's way of telling you that he can not answer the question.  You have to read between the lines.  I can't answer it either, but that is neither here, nor there.

Bill

MileHigh

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Re: Magnet Myths and Misconceptions
« Reply #1027 on: January 14, 2015, 05:26:56 AM »
You said no resistance so the only variable is Inductive Reactance which I am not going to give you an answer for!

To many un-knowns to give an answer that could be considered accurate.

Wire size could be 12Awg or it could be 32Awg, to many variables and this will change it all! Size of the coil, Length, W x H or 2piR...

The question has been fully defined.

So you see Chris, a circuit with a single lousy component, basically as simple as a circuit can be, and you are not capable of answering the question.

You are going to have to think about that one.  All your bluster and chest puffing and demeaning remarks, and you can't answer how a circuit works that consists of a single solitary inductor and a power supply.

EMJunkie

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Re: Magnet Myths and Misconceptions
« Reply #1028 on: January 14, 2015, 05:29:47 AM »
MH:

This is Chris's way of telling you that he can not answer the question.  You have to read between the lines.  I can't answer it either, but that is neither here, nor there.

Bill

No Bill - this is my way of saying that if you take my legs I cant walk.

Resistance is an important variable in knowing what current will be drawn. Anyone here will accept that fact, only you cant see this!

Inductive reactance is the other variable and it will be only a small part of the equation.

So if you think you're really smart now - You are still not!

MileHigh

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Re: Magnet Myths and Misconceptions
« Reply #1029 on: January 14, 2015, 05:31:49 AM »
How would inductive reactance relate to my circuit?

MarkE

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Re: Magnet Myths and Misconceptions
« Reply #1030 on: January 14, 2015, 05:31:51 AM »
MileHigh - Please describe what conditions the Power Supply is under during the Test, you said Variable! What is the variance due to the test and applied conditions - Not enough Information Provided.

Any coil that has a Voltage applied to it will see a Charging Time Constant!!! this is T=L/R - 5 Time Constants charge the Coil to 99.3% of its total applied charge vs the Voltage Applied. The Magnetic Field stores the Energy in the following formula: 1/2 LI^2

Current I would normally lag the Voltage by a phase angle. This would then catch up as the Time Constants move from 0.

Again you have not provided enough information as to why the Power supply shows a lower Voltage. I can only assume that its source impedance is to low for the current drawn.
Since MH did not specify the problem from negative infinity to positive infinity it is a time domain problem and no phase angle may be inferred.

MarkE

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Re: Magnet Myths and Misconceptions
« Reply #1031 on: January 14, 2015, 05:32:53 AM »
Before time zero the output from the power supply is zero volts.  Then for 5 seconds the output from the power supply is 7 volts.  After 5 seconds the output from the power supply is 5 volts.  This is a given.

There is no resistance anywhere in the circuit.
Resistance is futile!

MileHigh

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Re: Magnet Myths and Misconceptions
« Reply #1032 on: January 14, 2015, 05:33:34 AM »
Famous quotes:

Quote
All anyone here needs do is visit my site and they can see right away my site contains more about inductors than you will ever know in your entire life! So your stupidity has tripped you up yet again!

!Creo que no!

EMJunkie

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Re: Magnet Myths and Misconceptions
« Reply #1033 on: January 14, 2015, 05:34:31 AM »
The question has been fully defined.

So you see Chris, a circuit with a single lousy component, basically as simple as a circuit can be, and you are not capable of answering the question.

You are going to have to think about that one.  All your bluster and chest puffing and demeaning remarks, and you can't answer how a circuit works that consists of a single solitary inductor and a power supply.

MileHigh - I answered your question with MUCH better detail than you answered mine!

MileHigh - Please describe what conditions the Power Supply is under during the Test, you said Variable! What is the variance due to the test and applied conditions - Not enough Information Provided.

Any coil that has a Voltage applied to it will see a Charging Time Constant!!! this is T=L/R - 5 Time Constants charge the Coil to 99.3% of its total applied charge vs the Voltage Applied. The Magnetic Field stores the Energy in the following formula: 1/2 LI^2

Current I would normally lag the Voltage by a phase angle. This would then catch up as the Time Constants move from 0.

Again you have not provided enough information as to why the Power supply shows a lower Voltage. I can only assume that its source impedance is to low for the current drawn.

1: You did not ask for current:

Okay, here we go.

The circuit is just a variable power supply connected to a coil - that's it, nothing else.   The coil is 2 Henries.   The coil is an ideal coil with zero wire resistance.  The power supply is an ideal power supply with zero output impedance.

At the start of the test (time zero), the power supply outputs 7 volts.   After five seconds, the power supply outputs 5 volts.

Please describe what happens with this circuit starting from time zero.

2: you have changed what you are looking for half way though the test - This show what sort of person you really are!

I answered your question! Much better than you answered mine! I am right in what I answered! Anyone here can see this!

You have distorted this whole thing like I knew you would!

MileHigh

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Re: Magnet Myths and Misconceptions
« Reply #1034 on: January 14, 2015, 05:35:00 AM »
Since MH did not specify the problem from negative infinity to positive infinity it is a time domain problem and no phase angle may be inferred.

I am relying on the testee to make an intelligent assumption about time zero.  Or to ask an intelligent question.   :)