MH's ideal coil and voltage question

[wattsup]

I think the question is clear enough.  A voltage source is connected across an inductor.  The voltage is a step waveform with various voltage levels, what happens?

Some people didn't even know where to begin.  That is very telling.  What happens?  The only unknown is the current, solve for the current.

Honestly, all these words that you are throwing at my question itself are too much.  The question is what it is.

MileHigh

@MH

Your question really involves 6 different experiments, so it should have been questioned as such. Each one would start at their own t0 mark at their respective voltage setting and duration. Each would have produce their individual result. Your question the way it was inferred is that all these events occurred with only one 4V application and nothing else. After the 4V you did not say stop, reset the voltage to 0, wait x seconds, stop reset the voltage to -3, wait x seconds, etc. You said all these events occurred because of the initial first application of 4V. Now do you get it. I don't see why this is so hard to understand. 

If you were writing a technical report with such a question, you would have been fired the next day.

And please don't give this "If you were an EEer you would know what the question meant business". You were  not asking this question to known EEers you were asking it to @tinman and others here. Wonder why no one else dared answer it? Because they were to smart to get involved in the first place. Dumb me all right.

@tinman

Sine wave, square wave, will not change that the question was just badly presented. Since these are 6 individual experiments with the same 5H, there is no point to answer it anymore because the first 2.4 amps gave out the rest of the answers. hehehe

It helped Wattsup to notice that he needs to be more careful with his words.
These are technical posts and every word matters. Making mental shortcuts is sometimes funny but most often it requires "secret decoder rings" from the reader.  Those are not good habits for technical communication.

So now we have established that an ideal voltage source merely needs to have:
- zero internal resistance
- zero internal reactance
- an output voltage that is not affected by the load

...but it does not need to output a constant output voltage all the time, and it can be even an ideal alternating voltage source.

@verpies

I have always appreciated your input regardless of who you respond to it is always a pleasure. That includes @poynt99 and others who know who they are. But you all are not @MH and this is not your question.

So let me ask you this simple simple question.

You have an ideal voltage source of 4V and an ideal inductor of 5H. You apply the voltage at t0 for 5 hours. What will be the voltage read across the terminals at every hour? What will be the current measure at every hour?

You know why I made this easy. hahaha Here is my answer because it has already been said before. The voltage will remain at 4v throughout the 5 hours. The current will rise to 2.4 and remain there for 5 hours. Is this correct or not?

That's all we need to know to ascertain is @MH'S question was well presented of not.

wattsup

[MileHigh]

Wattsup:

No, the question involves one experiment.  A standard way to describe a process is chronologically, which is what I did.  Many people have no problem at all with the question.  I am attaching Poynt's graph that shows the voltage waveform that corresponds to the question.  There is no more need to discuss the question.

What we need is progress towards answering the question.

MileHigh

[verpies]

You have an ideal voltage source of 4V and an ideal inductor of 5H. You apply the voltage at t0 for 5 hours. What will be the voltage read across the terminals at every hour? What will be the current measure at every hour?
You know why I made this easy. hahaha Here is my answer because it has already been said before. The voltage will remain at 4v throughout the 5 hours.

Yes.
No load is incapable of altering the voltage at the output of an ideal voltage source.

The current will rise to 2.4 and remain there for 5 hours. Is this correct or not?

No, at t0 the current will be zero.
at 1h it will be 2.88kA
at 2h it will be 5.76kA
at 3h it will be 8.64kA
at 4h it will be 11.52kA
at 5h it will be 14.4A
...and it will keep increasing like that at the rate of 2880A per hour, ad infinitum.

[tinman]

Brad, verpies is agreeing that some of the energy stored in the inductor can be absorbed by the voltage source. Or at least I think he is.

What are your thoughts now?

My toughts are,because of MHs statement that an ideal voltage source contains no energy,is a clear indication that he would not have been able to answer his question correctly.
You may wish to rethink your stance on MH being able to do so.

Brad

[wattsup]

@MH

If you cannot first concede your question was loaded the way it was asked, then you can play with yourself

wattsup