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Any attempt to change the current flowing through an inductor sets up a counter-emf which opposes and slows down the change. The opposition is called the reactance (X). The faster the change, the higher the reactance: For a sine wave, X = 2pifL. Hence a fast-changing signal passes more easily though a path of low inductance than through one of higher inductance.
High inductance = high reactance. If an alternate path with lower reactance exists, the signal will follow the path with lower reactance. For a basic understanding, consider resistance same as reactance. Alternate path means another parallel connection. If two resistors are there in parallel, more current will flow via the resistor with lower resistance.
High inductance = high reactance. If an alternate path with lower reactance exists, the signal will follow the path with lower reactance. For a basic understanding, consider resistance same as reactance. Alternate path means another parallel connection. If two resistors are there in parallel, more current will flow via the resistor with lower resistance.
I agree that current flows via lower resistor path. But When it comes to high speed signal does it follow the same.???
Because what I think is reactance is directly proportional to either frequency or inductance , when frequency is high then reactance is high and so inductance will be low.
Is this concept correct ???
For an inductor(solenoid) Reactance = XL=2·pi·f·L where L is the inductance.
The inductance (L) is determined by the shape of the inductor (which means, you build up an inductor, and because of it's shape and wire used etc... you got an inductance). The dual for the inductance is the capacitance of a capacitor (C) where the capacitance is determined by its physically construction (dielectric material, distance between plates, if has a cylindrical shape etc.).
Reactance is the opposition of a circuit element to a change in current or voltage, due to that element's inductance or capacitance respectively.
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For an inductor, the reactance is called "inductive reactance" and for a capacitor is called "capacitive reactance" but you can refer to it with the general name "reactance".
In general this is not true. In a capacitor, there is a dielectric with a dielectric constant which is a complex term. For an inductor, there is a permeability that too is a complex quantity. Except in the exceptional case where the dielectric (or the core of the inductor) is vacuum, the dielectric constant (or the permeability) is frequency dependent. The imaginary part of the permeability is responsible for the dissipation and for the frequency dependence of the inductance. We always have air core inductors made of thin wires of high electrical conductivity. For an ideal capacitor or an ideal inductor the permittivity or the permeability is always real.
"reactance does not change inductance" is a matter of definition. Reactance is defined in terms of inductance and not the other way.
I was trying to deal with the OP's misconceptions about fundamental properties and wanted to avoid confusing the issue with all those finer details. We could also say that a high voltage can change the effective resistance of a real-world resistor through heating and internal arcing, but we're not discussing the imperfections of real-world components here.
In the OP's second post, he showed that he had the idea that inductance decreases because reactance increases at high frequency. I still maintain that this is untrue and is not a matter of definition. The OP's statement would be something like saying that, since a low voltage causes low current to flow through a resistance, then it increases the resistance, which is nothing more or less than a misconception.
I too agree. His basic question itself is wrong. He should have asked "High-speed signals follow the path of least impedance" rather than "High-speed signals follow the path of least inductance"
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