MH's ideal coil and voltage question

[tinman]

Tinman,

I did not notice the short circuit you drew into your diagram.  I mistook those arrows for measurement points (only glanced, time is short right now).



PW

Surely you do not believe that is the equivalent circuit for an ideal inductor with zero resistance.

You forgot to take notice of the rest of the circuit described in MHs question.
This is what i have been trying to explain all along.
That will come soon enough.

Question 2--see diagram below.


Brad

[picowatt]

You forgot to take notice of the rest of the circuit described in MHs question.
This is what i have been trying to explain all along.
That will come soon enough.

Question 2--see diagram below.


Brad

Why do you indicate a wire shorting your coil?  You do know that does not represent an ideal inductor don't you?

As you did not specify an ideal wire, just one with no resistance, shall we assume the wire still has inductance (like any wire)?

PW

[picowatt]

You forgot to take notice of the rest of the circuit described in MHs question.
This is what i have been trying to explain all along.
That will come soon enough.

Question 2--see diagram below.


Brad

My short answer to question number two as stated in the diagram is yes.

PW

[wattsup]

@tinman

For your last question, my answer is yes there will always be some form of impulse voltage but nothing that could be considered as gain since the short is bleeding it right away. This would somewhat equal your Lewan test.

@all

OK, then let me ask you guys this crazy question if possible. We will call it a Bizarre Four Stage Coil (BFSC). It is not an ideal coil, just a regular coil with regular copper wire of let's say 16 awg. You can give it the resistance value you want, it should not change the question.

You apply a DC voltage on the BFSC where in the first quarter of the coil the voltage can exist as applied, in the second quarter the voltage cannot exist, in the third quarter the voltage can exist again as applied and in the final quarter the voltage cannot exist again. What is meant by cannot exist just means the voltage will be zero on those quarters of the coil but will not hinder the voltage from continuing to the next quarter as if the previous quarter was not there. This would infer that the voltage would be as applied through the first and third quarters as if the second quarter was not there although the second and third quarters are there but at zero volts. Zero here should not infer infinity.

The inductance of the total coil is 1H. You apply a DC voltage of 10 volts at 5 amps.

The question is what will the current be in each quarter?

Also, to prevent any "that's impossible" drama you can modify this question any way you want as long as you keep the four quarters and their voltage handling attributes.

I will tell you in advance that this is not a trap question but it will lead to a second question that you may not like. This is an example of puzzles I make for myself to verify EE logic. Let's see how objective you guys really are. You can't get more basic the this while still providing a spread that can actually be discussed.

wattsup

[tinman]

Why do you indicate a wire shorting your coil?  You do know that does not represent an ideal inductor don't you?

As you did not specify an ideal wire, just one with no resistance,

PW

As we are talking about ideal inductors,i thought you would have nutted that out for your self.\If we are talking about an ideal coil,would it not be wound with ideal wire?--that has no resistance?.

shall we assume the wire still has inductance (like any wire)?

Makes no difference to the answer to the question.

This is a simple test that can be carried out on the bench using a real coil,and provide the correct result.


Brad