# Tag Info

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Right now, there's nothing connecting the +1V node to anything else on the circuit, so we can delete it. There's nothing connected to the V node, which means we can eliminate that leg. There's nothing connecting the pins (the unfilled circles) to anything, so the leg between the +2V node and the filled circle is a short (it's all the same voltage). So ...

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It seems like 60 Hz may have been selected instead of 55 or 75 simply because there are 60 seconds in a minute and so 60 cycles per second seemed a comfortable number. During the early days of distributed power transmission the frequencies and voltages would have been all over the place. The limits of what was safe and convenient would have been developed ...

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https://www.quora.com/Why-does-the-United-States-of-America-use-110-60hz-power-and-why-does-India-use-230-50hz-power Synchronous clocks rely on the 50 or 60 Hz utility frequency of the AC electric power grid as a timing source, by driving the clock gears with a synchronous motor. They essentially count cycles of the power supply. While the actual frequency ...

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The disadvantage of having too low a frequency is that the mains transformers become very large. However there have been lower frequency standards (25 Hz, 15, ect.) These are used by trains (mostly legacy systems).

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The bulb is intended to operate using a particular source voltage and frequency. (For example, 120 V of 60 Hz single-phase AC.) Under these conditions, the bulb is expected to use an average of 10 W of electrical power. (The power usage might be different while the bulb is warming up after being turned on, or while the filament is exploding while burning ...

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Practical reasons include the skin effect (you do not want your frequency to exceed at most a few KHz by much unless you are willing to use something akin to Litz wire to transfer large currents) and the size of magnetic cores for transformers, which must be able to magnetically store more than the maximum energy to be transmitted in each cycle, such that ...

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The two other answers address the frequency issue. The voltage issue is much simpler. If the voltage is too high, you run the risk of arcs between conductors. The minimum distance between conductors before an arc appears is proportional to voltage. At 240V, you arc at a distance of a few millimeters in air, depending on humidity. More voltage gets clearly ...

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In the end, the choice of a single specific number comes from the necessity to standardize. However, we can make some physical observations to understand why that final choice had to fall in a certain range. Frequency Why a standard? First of all, why do we even need a standard? Can't individual appliances convert the incoming electricity to whatever ...

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Why is mains frequency 50Hz and not 500 or 5? Engine efficiency, rotational stress, flicker, the skin effect, and the limitations of 19th century material engineering. 50Hz corresponds to 3000 RPM. That range is a convenient, efficient speed for the steam turbine engines which power most generators and thus avoids a lot of extra gearing. 3000 RPM is ...

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Let a square conductor frame length l, resistance R,be pulled out with a constant velocity v from a magnetic field B perpendicular to plane of the frame .Then an emf e=Blv is produced across the frame. The EMF is around a closed loop. It is equal to the force per unit charge around the loop. So for instance \mathscr E=\oint_{\partial S}\left(\vec ...

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What is potential difference? It's pretty simple, actually. a charge repels other like charges (with same sign). That means, an electronic repels other electrons. if you at one point have, say, 10 electrons then they will try to move as far away from each other as they can. this point of many electrons (that is, this point that electrons are strongly ...

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Theoretically, these requirements arise from the way you connect the measurement devices to the rest of the circuit. A voltmeter is connected in parallel, as you said. Say that you are trying to measure the voltage drop across a resistor $R$ through which passes a current $i$. If the internal resistance of the voltmeter is comparable to $R$, then the ...

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a resistor reduces the potential energy of the current across it, then the current that leaves the resistor will have less potential energy and thus, less pressure or voltage. The current does not have potential energy, the electric field does (the potential being exactly its potential as in the sense of differential forms). If one resistor only ...

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I know I'm a little late, but I'll take a shot at answering this for you. I'm actually very much a beginner at understanding electronics myself, so everyone: please keep me honest! There has been some criticism of your question, as it does not show a complete circuit. I need to agree with this, as any reliable calculations within a circuit require ...

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Your question could use a context to be more clear. But I think you mean that the battery supplies a certain $\mathrm{emf}$ to the circuit, and the circuit elements require a certain voltage $V$ for the current to run. Now, if the voltage $V$ over all circuit elements (summed up) is less than the $\mathrm{emf}$ supplied, then some is lost. Meaning, some ...

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Your question makes no sense. Volts is merely a common unit EMF is measured in. To say that volts means a different kind of energy per charge than EMF is just plain wrong, making your question non-sensical.

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It appears to me that you are slightly confused with regards to the concept of current in conductors. Now, if I only choose one side of this rectangle, and apply external electrical field ∑ only to it, what EMF would I create on the conductor? I would simply say ∑, however then I had the following idea, and I started to doubt if I create 2∑ instead ...

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The ground is connected to every point of the metal plate by the metal wire and the metal plate. I mean, there is a metal wire that connects the ground to the plate, and then there is the metal plate that connects every point on the metal plate to each other, therefore every part of the metal plate is equally connected to the ground. When you touch the ...

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