MH's ideal coil and voltage question

[MileHigh]

Please solve for R=0,so as we are defined to the parameters of your original question,as i have shown you already the infinite difference this makes even at a resistance far less than .001 ohms

Brad

You are shooting blanks, we are not discussing resistors.  What I did was compare the behaviour of the ideal 5 Henry coil and a real 5 Henry coil (0.001 series resistance) and showed you that their behaviour is nearly identical at t=1 second.  Do you get that?

If you get that then it proves to you that the formula for the current through the ideal coil of i = 0.8*t is correct.

In other words the explained behaviour for the ideal coil is not a short circuit or an open circuit, it's i = 0.8t.  Do you get that?

If you get all of this then you should move forward and try to answer the full question and demonstrate that you know what you are doing.

[MileHigh]

Magneticitist:

Stop the psychobabble and the drama, ok?  The thread is here and Brad started it and that's all there is to it.

Do you want to contribute to it and learn?  Then work with Brad and see what you can come up with.  Try to answer the question and use that as a vehicle to learn.

MileHigh

[tinman]

You are shooting blanks, we are not discussing resistors.  What I did was compare the behaviour of the ideal 5 Henry coil and a real 5 Henry coil (0.001 series resistance) and showed you that their behaviour is nearly identical at t=1 second.  Do you get that?

If you get that then it proves to you that the formula for the current through the ideal coil of i = 0.8*t is correct.

In other words the explained behaviour for the ideal coil is not a short circuit or an open circuit, it's i = 0.8t.  Do you get that?

If you get all of this then you should move forward and try to answer the full question and demonstrate that you know what you are doing.

Tau=L/R is how the time constant for the rise of current flow is determined,and that time constant has a value of infinity,and only changes to a finite value when a small amount of resistance is added to the inductor.

The second thing to ask your self,is how is the inductor defined as being a value of 5 Henry's when you have no resistive value to make that definition?. As you can see,the inductance in all three example in the link below,rely on measuring a voltage drop across a resistance to obtain the current flow to obtain inductive value. So how is this done when there is no resistance? When you work this out,you may begin to understand as to why an ideal inductor dose not dissipate any power,which also lines up with your very own statement that a voltage cannot be measured across an ideal inductor when a DC current if flowing through it,as current alone is not power,and hence the reason that an ideal inductor dose not dissipate power. But now your question also posses the problem that we !do! have an ideal voltage across the ideal inductor that you say has a DC current flowing through it. It can only have a voltage across it if there is no current flowing through it-and visa versa .
http://www.wikihow.com/Measure-Inductance

It is like my answer says it is--you cannot place an ideal voltage across an ideal inductor,as an ideal inductor dose not exist.
I have also shown that regardless of how little the resistance value may be,it will lead to a value that is infinitely different to that of an ideal inductor that has no R value.


Brad

[MileHigh]

What does DC current have to do with anything when you put voltage across an ideal coil?   You will have to contemplate that.

You have been given more than enough information to do some hunting and researching on your own so that you answer the question correctly.  You still haven't taken a stab at the full question.

After all this, it still feels to me like there is faint hope that you are going to achieve those two tasks I listed for you with your current attitude.  You never know though like I already said.  I think that you are going to have to hope a guru comes in to help you because I am jumping off the train and switching to passive observer mode.

I hope one day in the not too distant future to see you follow-up on both tasks successfully and demonstrate full competence in this very important subject matter.

MileHigh

[Magneticitist]

I'm just an oaf but I get what you're saying.. an inductor requires at least some form of 'resistance' to have a measurable inductance otherwise we are just saying "hey this is a 5H inductor" and base that entirely off of speculation.