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When there is a change in magnetic-flux, based on Faraday's law of induction & Lenz's law, we know that there is change in Potential Difference now, aside from the source V now we have a induced −V due to the change in magnetic-flux, and it opposes the current, why would it? I understood from lenz's law that it will, but not great detail as to why. ...


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Consider for a moment, a cell that is not connected to a circuit, i.e., there is no path for current external to the cell. The chemical reactions inside the cell remove electrons from the cathode and add electrons to the anode. Thus, as the chemical reactions proceed, an electric field builds between the anode and cathode due to the differing charge ...


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You're so close to the answer I'm not sure how to nudge you along without basically just giving you the answer. I'll try anyways. There are some troubling conceptual mistakes you've made in an otherwise straightforward derivation. For starters : The reason I don't set $E_0 x_0$ to zero is because there is no $1/x$ term; otherwise I'd be able to make the ...


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When we derive Ohm's Law using the Drude Model, we assume at one point of time that E=V/L, when is fact, E=dV/dL, unless E is constant, in which case the assumption E=V/L is true. But I don't understand why the electric field in a conductor must be constant as current flows. Generally, the electric field in a conductor does not have to be constant (in ...


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An easy way to prove Ohm's law for electric fields that aren't constant is to first assume that the electric field is approximately constant over short lengths, just like $E=dV/dL$ suggests. Using that, you can derive Ohm's law for short lengths of material, $dV=IdR$. We'll assume that "current in = current out", which is true at steady-state. This allows us ...


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What is voltage? The way I see it, and this is only my concept, voltage represents electron pressure. because electrons repel each other,the more electrons you pack into a unit mass of a conductor the higher the voltage, such as in a metal foil capacitor. If you force electrons onto a non conductor, the room for electrons is very limited and the static ...


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This might help understand why the current also obeys a wave equation. The voltage is essentially the gradient of the electric field. So if you have an oscillating voltage, you are trying to set up an oscillating electric field in the wire. The current is related through Ohm's law $\mathbf{J} = \sigma \mathbf{E}$. Now, you cannot have an instantaneous change ...


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The term Resistance does not come into play while dealing with Photoelectric Effect. The latter is related to the emission of electrons when the surface of a metal(or any substance) is hit by photon particles(photon is the unit particle making up the light that we talk of). Here the more important concept is that of Work Function, i.e. the minimum amount of ...


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does this mean that Ohm's law just fails in this case Ohm's law is not universal. The ideal resistor circuit element is defined by Ohm's law but not all circuit elements obey Ohm's law; Ohm's law only applies to ohmic devices. Physical resistors and conductors approximately obey Ohm's law but, for example, semiconductor diodes, transistors, ...


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You are right that you should solve the Maxwell equations for air + metal wire, not just for air, but the solutions for the cylindrical metal wire + air give phase velocity component along the wire close to c (or at least of the same order of magnitude), as far as I understand (http://www.mathunion.org/ICM/ICM1924.2/Main/icm1924.2.0157.0218.ocr.pdf )


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If there's a way to solve its by assuming both ammeters to be identical and thus from your equations:$$0.2R+6=1.7R\\\implies R=4$$ because there's no other relation between them, or if you find one it'll be the same information disguised in other form. or it can be solved if we have any bit extra information; as to solve a linear equation in two variables ...



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