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One could say that the AC current is steady if its RMS (Root Mean Square) value is steady. So in a statistical sense it's steady. It's most likely a matter of semantics than definition. Or a different definition for the particular application.


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We might think of the integral form of this $$ \oint\vec H\cdot d\vec l~=~\int\int\vec J\cdot d\vec s $$ We have two integrals, on a line integral and the other an area integral. With each unit of line $d\vec l$ this is projected onto the mangetic field $\vec H$. Each $\delta l$ length is associated with a pie shaped region with area $ds~=~\frac{1}{2}rdl$ $=...


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It's prettily answered by user35952 in his comment above; nevertheless here comes the explanation: The relation $$\nabla\times \mathbf E= 0\qquad\qquad:\qquad\qquad \textrm{True only for statics}. $$ The general relation is $$\nabla \times \mathbf E= -\partial_t\mathbf B\;.\tag 1$$ The static fields were conservative and hence could be expressed solely ...


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I did a bit of research and will give my own answer to my question for those that are interested. The return current follows the path of least impedance in the ground plane. There are two sources of impedance: the resistivity of the conductor, and the coupling between the trace and the ground plane: $$Z = R + jX\omega$$ At low frequencies the resistivity ...


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Actually charges do accumulate even around a resistor. Consider the following model: two conductors with resistances $R_A$ and $R_B$ and lengths $L_A$ and $L_B$ are connected to each other, and a potential difference of $\Delta U$ is applied to their free ends. By Ohm's law we have: $$\Delta U_A=IR_A,$$ $$\Delta U_B=IR_B.$$ This means that, for equal-sized ...


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I think it is easy to understand. Here I am giving a heuristic picture, current in any wire is generated by charge flow. $I=\frac{dQ}{dt}$ now if you apply alternating current on the sides of capacitor you will find that charge on one plate is constantly increasing and decreasing, which induces the opposite charge on the other plate changing with same rate....


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This is a really common effect observed in high-frequency circuits, and it's often the difference between a good one and a noisy one. There are two relevant length scales in this problem: the first is the distance between the plane and the conductor, and the second is the wavelength of the electromagnetic waves being generated by the circuit. If you're ...


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The flaw in your reasoning is in assuming that there are no magnetic fields inside the conductor. Equilibrium electric fields cannot exist in a perfect conductor, but magnetic fields can as long as they are not changing in time. Empirically, the charge density is quite uniform through the wire's cross-section, so the current does indeed flow through the ...


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There's something called the skin effect which is roughly what you described in your question. The skin effect forces charges to aggregate on the surface of a conductor. How far from the surface the charges exist is called the "skin depth", which has a low-frequency approximation of $\delta = \sqrt{\frac{2\rho}{\omega \mu}} $. For a perfect electrical ...


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If your question is: does changing the resistivity (rho), while keeping the same the shape of the resistor, linearly affect the total resistance? Then the answer is yes. The "const" in your formula is then determined by the shape of the resistor. If your irregularly shaped resistor is much longer than it is wide, and the width does not change fast, its ...



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