# Tag Info

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If the electric charge from lightning is captured and harnessed through circuits, eventually it will reach the ground, but once there it will join the general discharge process mentioned by Feynman. It won't lead to any build-up of charge. Incidentally, it would be very difficult to harness lighting with sufficient regularity to make a difference to the ...

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There is a grand tradition in electromagnetism to talk about the electric fields using the same terminology as we use for velocity fields. For instance we talk about the flux which rightly is a flow per area (and sometimes we multiply by the area and still call it a flux, which is even more confusing to call two things a flux) but it isn't a flow because it ...

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How quickly discharge will occur in the situation you sketch depends entirely on the surface properties of the negative electrode. For current to flow, electrons need to be released from the negative electrode; once they are free, they will accelerate unimpeded to the positive electrode. They will arrive there with 1.5 eV of energy, causing a small amount of ...

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You are taking a shortcut when you say, "The voltage is zero." Voltage is always measured between two points. In electrical engineering, when we say the voltage at point X is V, we actually are measuring the voltage between point X and an implicit other point called "ground". In the electric power grid, "neutral" is ground, by definition. So the voltage ...

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Is the working principle of light bulb reversible? No. Electric potential energy is converted into thermal energy in the light bulb filament. At a certain temperature range the filament will light up; that is, it will radiate with a wavelenght in the range of visible light. That this process is non-reversible might be clear if you consider some more ...

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The exposition you give is fine in classical physics. Note though that in classical physics a particle cannot be a point particle, because something has to carry the charge in classical physics formulations. So the fact that one finds infinity at r=0 just hits on this constraint. One could use the argument as a proof by reductio ad absurdum that particles ...

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When considering whether two surfaces will have a high friction or a low friction when rubbed together, more important than whether they are individually smooth or rough is what the barrier to their passing actually is. Consider first two perfectly flat plates. Even if the two plates are made out of wood, which is rough, they slide relatively easily past ...

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The lightnings primarily depend on strong electrostatic fields. They're up to 100 volts per meter in the summer and 500 volts per meter in the winter. These fields are fluctuating. When a certain critical threshold not far from those values is reached, a lightning strikes. Does the electrostatic field move a metal? There is no direct electrostatic force ...

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In vacuum there are no charge carriers like ions or electrons. With nothing to carry charge, i.e. current, such a battery would discharge much, much slower than when the battery poles are connected by something that can carry charge like a conductor or an imperfect insulator.

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Lines of electrostatic force exist between the positive and negative poles of the battery, even though they're separated by a vacuum. Vacuum permittivity is ε0 = 8.854 * 10^-12 farads per meter. By convention, this is called the dielectric constant of 1, a baseline against which the dielectric permittivities of other materials are compared. ...

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I think this picture answers the question There battery's terminals are not charged. It's just a chemical reaction that starts the charge. There's a Zn and a CuSO4. When they meet each other via a cable, the Zn gives 2 electrons to ChSO4. Cu gets rid of SO4, leaves 2 extra electrons to SO4 and takes the 2 electrons it got from Zn. Then we have SO4 ...

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If by our goal is to see the fields due to some charge or current, look at Jefimenko's equations. For electric fields electric field they can be caused by charge density, the rate of which charge density changes or by the rate that current density changes. For magnetic fields they can be caused by current or by the rate at which current changes. Since you ...

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A metal conducts quite well because the there is an electron band that crosses the Fermi level. So, electrons can easily be excited to increase their momentum a bit and consequently move in one direction. Now if you add one electron to the wire, the Fermi level rises. However, you would not be able to see the increase caused by one single electron (or a ...

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My brother-in-law faced this EXACT problem, as he worked on high tension lines. There is a corona discharge from these lines due to the very high voltages involved. From experience, the linemen learned that this corona discharge is injurious to internal organs. To prevent injury, the linemen wear the Faraday cage suit, because such a suit keeps the ...

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If I understand your question correctly, the answer is "yes". For most energy conversion processes, the "inverse" process exists. Typically though, as you go from one to the other, and back again, you will lose some efficiency - think of it as the universe entropy increasing at every step of the way. Specifically, with regard to your two examples: The ...

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Like all steady state circuit analysis things in parallel share the same voltage, and things in series share the same current. The question then really boils down to what the current vs. voltage curve looks like for a solar panel. A quick search turned up this: from https://www.folsomlabs.com/modeling/module/module_model So in this case it looks like you ...

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The problem is in your assumptions. If you have an E-field in the loop then the potential (voltage) would be increasing as you go around it. If you have a current in the wire, there must be a magnetic flux through the loop. The magnetic field has energy, which you are not accounting for. The magnetic field cannot penetrate a superconductor, so it is ...

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So my question is where I am wrong or more appropriately what wrong steps I have made in my calculation. When you lower mathematically the resistance while fixing the current, this means electric field decreases, but magnetic does not. In the limit $\rho\rightarrow 0$ all the initial energy is in the magnetic field and can be expressed through ...

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I think an insulator does not completely stop charge transfer, if viewing it to act in the same way as maybe ie. a thermos cup, which does significantly increase the cooling time of a hot coffee inside, but does not fully prevent heat from escaping, hence allowing the hot coffee/material inside to cool.

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Static electricity is not like regular electricity in that it does not involve closing a complete circuit; it just needs a large difference in voltage potential between one object and another. When you shuffle your feed on a nylon carpet and touch your finger to a doorknob, you are not closing a circuit. Instead, you are building up a large negative charge ...

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Your description is not very complete, but I guess what happens is exactly what you expected: to get significant repulsion (to counteract the atmospheric pressure), you need very high charge, which will be necessarily limited due to air discharge (maybe that is why you observed sparks). I don't see how replacing an aluminum shell with a plastic bag ...

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When you rub your fingertips along a blanket you are exchanging charged particles like electrons and in some cases molecules missing an electron. This is due to friction. If you notice your fingers will actually become very hot if you do this over and over. These electrons are negatively charged and create what we call an electric field around them which ...

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Electrons (and other charge carriers, e.g., ions) in vacuum travel without resistance. However, as pointed out, correctly, in the other answers, there are no charge carriers in vacuum. Nevertheless, electrons can escape from the terminals if they have a kinetic energy which is bigger than the potential barrier of the terminal surface, i.e., the work ...

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