don't know if this is the right board for this- maybe should

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bump

>>7714839
Does the impedance has something to do with wire's length?

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plz, i'm considering taking the problem to /b/ and just watching the poop-show into which the thread will degenerate

>>7714860

I'm given to understand, yes

http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/indcur.html

Although I don't think this will really help you if you're trying to do a micro coil

In an ideal world, that should work out. In reality, you will get terribly different inductance for the two coils (assuming they are small and hand wound).

>>7714876

it's not so much about building the coil as it is about "is my first post wrong, tho?"

>>7714881

but the "math" for lack of a better word, is sound?

If you're dealing with direct current the answer is pretty simple. All wires have a given amount of resistance, which is probably listed by the manufacturer. This resistance is measured in Ohms per meter (or whatever imperial unit).

For circuit elements in series resistance adds up simply: R1 + R2 + R3 etc. For elements in parallel the resistance adds up reciprocally:

1/R-total = 1/R1 + 1/R2 + 1/R3 etc.

Because of this, in most cases elements connected in parallel will have lower resistance than any individual element in the circuit. The more splits in your circuit, the lower the resistance will be overall. BUT the current in your overall circuit will also be lower overall assuming that the voltage stays the same.

If your're dealing with AC then things get more complicated as you have to deal with things like back EMF and inductance.

>>7714887

assume there are no other complications and the rest of the world is perfect...is the first post correct?

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>>7714870
Indeed , its correlated with resistivity coeficient which is measured in ohm/meter

Ah , finally my autism moment
Pic unrelated

>>7714886
If it is DC and we can assume the self-capacitance of the coils is negligible, definitely. If it is is a clean AC signal, it also works out since halving the length should also halve the inductance.

>>7714876
>>7714881
>>7714887
>>7714899
>>7714903

beautiful, thanks a ton guys

now i can go tell my friend he's a frickin idiot

>>7714882

I think you were ok up until the last line. The inductance of the coils, assuming minimal conductance between the adjacent wraps (which, like I said, will not be the case if you're doing a micro coil), won't depend on the length of the wire, but rather on the number of wraps and the length of the coil. Check the link I posted.

The complex impedance of an inductor is s*L, so halving the inductance will also half the impedance.

>>7714913
Forgot to mention though, that this only considers the inductance. The resistance would probably be halved, but not the impedance.

>>7714913

so if (x) and (0.5y) then (0.25z)?

>>7714913
If we assume that halving the length of wire used, you simultaneously halve the number of loops and the length of the solenoid in a perfect situation. As a result, you halve the inductance.

>>7714917
Your correct, that two components of equal impedance in parallel will have a combined impedance of Z/2

Changing the length of the wire will change the real part of the impedance, but if you still build the coil with the same number of wraps, the imaginary part won't change.

On the other hand, if you only change the number of wraps, then the imaginary part changes, but not the real part.

>>7714918
Not if you change the radius of the coil, or if you change the length of the tails (both of which people do with their vapes).

>>7714927
Things like this are why I added a disclaimer about real coils.