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It sounds like you're asking "If two conductive materials are brought in contact, and one of them is electrically neutral, and one is positively charged, which direction will charge flow?" If that is indeed your question, then the answer is that negative charges (electrons) will flow from the neutral object to the positive object until they are at the same ...


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It all depends by what you mean by the word "flow". Let the charged body which is assumed to be a conductor produce an E-field. In a conductor which has mobile charge carriers then the charges can be made to flow within a conducting body which has no net charge. If you subject an uncharged conducting body to an external E-field then the mobile charge ...


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You've asked some really good questions here. Before starting, I want to first mention that the traditional picture of particles moving through a wire in electostatics is missing some physics; for instance, it ignores the quantum mechanical nature of electrons. The reason we still teach this model is because it captures the main effects (the phenomenon of ...


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You are correct, electric current consists of electrons travelling from one place to another. Some materials conduct electricity better than others. Copper is one of the best and that's why our conductors are usually made of copper. Aluminium is also very good (so is silver) and high-voltage cables are usually made of aluminium. However, everything conducts ...


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You set up a circuit which contains the galvanometer and adjust the circuit so that the deflection on the galvanometer is a maximum (for greatest accuracy). A calibrated resistance box is connected in parallel and adjusted until the deflection on the galvanometer is half of the deflection with no resistance box. In this condition the resistance of the ...


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The net effect of the charging process is the movement of electron from one plate which then has a net positive charge to the other plate which then has a net negative charge. The battery facilitates this by creating an electric field in the wires and it is this electric field which applies forces on the electrons which makes them move. The movement of ...


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The reason to use the alloy is because it has a much higher resistivity than copper and so the alloy wire will have a higher resistance which with standard laboratory apparatus can be measured more accurately. I also seem to remember that the temperature of coefficient is lower for some of these alloys ie for a given increase in temperature the resistance ...


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Your confusion is between two related concepts. Power dissipated in total = internal power + external power. If that is the power you are talking about, then an external short circuit will maximize the current and therefore maximize total power, $V\cdot I$. Power delivered to the load. That is the thing addressed by the maximum power transfer theorem, and ...


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To be clear, you can use Ampere's Law: $$\oint \vec B\cdot \mathrm{d}\vec\ell=\mu_0I_\text{enc}.$$ Specifically, it is the form without the displacement current, and it works because you are in magnetostatics. And Rob Jeffries' answer is totally satisfactory. But to specifically address your concern with the charge build-up lets look at an example of a ...


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Current is defined by the movement of charges from one point to another, and the concept is independent of a medium, or the charges being electrons. In this context the current is constituted by the uniformly moving charge. And that is why an uniformly moving charge doesn't create any radiation, as what happens to be a current in one frame is stationary ...



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