Joule Thief 101

[tinman]

The question

You have an ideal voltage source and an ideal coil of 5 Henrys.  At time t=0 seconds the coil connects to the ideal voltage source.  For three seconds the voltage is 4 volts.  Then for the next two seconds the voltage is zero volts.  Then for two seconds the voltage is negative three volts, and then for the next six seconds the voltage is 0.5 volts.  Then after that the voltage is zero volts.

Then you decide to change the question,before you have answered the original question.

Let's change it up and make it more difficult, and revamp the question:

Why? ,when you have not answered the original question?.
Your revamp question-->

You have an ideal voltage source and an ideal coil of 5 Henrys.  At time t=0 seconds the coil connects to the ideal voltage source.  The voltage source waveform is 20*t^2.  So as the time t increases, the voltage increases proportional to the square of the time.

The question is what happens starting at t = 0

The answer:

The current through the ideal coil starts from zero at time t = 0 and then increases with this formula:  i = 1.33*t^3.

Time..........Voltage.........Current
0...............0.................0
1...............20...............1.33
5...............500.............166.67
10.............2000............1333.33
20.............8000............10666.67
50.............50000..........166666.7

There you go, harder question answered.

There you go.
Original question not answered-as expected,and the harder question was answered incorrectly--very wrong

I am not sure what to say, I am not sure you correctly processed what I posted.  Perhaps try again tomorrow when the neurons will be firing differently?
<<< 1-An ideal voltage is one that dose not change in selected value. >>>
After six years you are lucky that you still have people that want to work with you and make attempts to help you.

We will see how your judgement on me go's MH.
Here is the correct answer to your question.
When a continuous current is flowing through an ideal coil/inductor,there is no voltage across it,as the resistance value across that ideal coil/inductor is 0.
If there is a voltage across the coil/inductor,then the coil/inductor is not ideal.
If there is no voltage across it when a voltage is applied to it,then the coil/inductor is ideal,and the voltage is not an ideal voltage.
Looking at your question again-->

You have an ideal voltage source and an ideal coil of 5 Henrys.  At time t=0 seconds the coil connects to the ideal voltage source.  For three seconds the voltage is 4 volts.  Then for the next two seconds the voltage is zero volts.  Then for two seconds the voltage is negative three volts, and then for the next six seconds the voltage is 0.5 volts.  Then after that the voltage is zero volts.

The parts i have highlighted are impossible if the coil/inductor is ideal--this is a fact.

So i ask again MH--what happens when an ideal voltage is placed across an ideal coil/inductor?
What happens when an unstoppable force meets an unmovable object?.

Im giving you a second chance to get it right.


Brad

[MileHigh]

We will see how your judgement on me go's MH.
Here is the correct answer to your question.

If there is a voltage across the coil/inductor,then the coil/inductor is not ideal.
If there is no voltage across it when a voltage is applied to it,then the coil/inductor is ideal,and the voltage is not an ideal voltage.

Looking at your question again-->

The parts i have highlighted are impossible if the coil/inductor is ideal--this is a fact.

So i ask again MH--what happens when an ideal voltage is placed across an ideal coil/inductor?
What happens when an unstoppable force meets an unmovable object?.

Im giving you a second chance to get it right.

Brad

Six years' worth of working on a bench and having lots of good people helping you, and all that you got out of it was a lousy t-shirt, right Brad?

You have pretty much destroyed yourself.  It's like you are going to have to start over from scratch.  Get Google and YouTube fired up and read, watch, and learn.  Take notes.

[minnie]

  Tinman, how's about trying an Edward M. Purcell?
         J.

[tinman]

Six years' worth of working on a bench and having lots of good people helping you, and all that you got out of it was a lousy t-shirt, right Brad?

You have pretty much destroyed yourself.  It's like you are going to have to start over from scratch.  Get Google and YouTube fired up and read, watch, and learn.  Take notes.

Your a fraud MH.
Show me any scientific paper that shows that a voltage can exist across an ideal coil/inductor.
You epic failure.

And to think you thought you could judge others on this question of yours,when you failed to answer it correctly.

I bet EMJ and Wattsup are having a good laugh now.

You are now the laughing stock of this forum.
A voltage cannot exist across an ideal inductor when the current flow is constant-period.

Post 2313-->You have an ideal voltage source and an ideal coil of 5 Henrys.  At time t=0 seconds the coil connects to the ideal voltage source

What do you make of Poynt's comment on post 2334--perhaps he can clarify?

Quote--> :At t=0, I think the universe might blow up   

What dose happen when a unstoppable force (your ideal voltage),meets an unmovable object(your  0 resistance-ideal coil/inductor).


Brad

[tinman]

  Tinman, how's about trying an Edward M. Purcell?
         J.

I see your back to your good old self again John.

Perhaps you should just google ideal coils/inductors-->it's that simple.


Brad