# Tag Info

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The force between the charges goes to zero. To see this, work in the frame of one of the charges. From its perspective, the other point charge is moving rapidly away, and the field of a moving charge is weaker along the direction of motion, as shown below. One cheap way of seeing this is to pretend the field lines have been "length contracted". For ...

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Conduction in water is mostly ionic - for pure water you have a very small fraction of ionized molecules (about 2 parts in 10$^{-7}$), so conductivity for pure water is poor. Add a little electrolyte (for example NaCl) and conduction improves. But in an ice crystal, the molecules / ions cannot move, so the main conduction mechanism is disabled. In that case ...

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@CuriousOne is approximately right. Others have thought of it, the url below is a paper from one who concludes with slightly more careful calculations (but still relatively straightforward) that the most one could get in terms of a continuous power from it is 50 MW, and typically a lot less. 50 MW is 5% of a large power plant. http://www.electrostatics.org/...

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For an applied AC voltage, the primary coil has an impedance from self-inductance which limits the current (amperes) flowing through the copper (unless you draw current from the secondary coil). For an applied DC voltage, the impedance from self-inductance is zero, which causes a large current to flow. This current heats up the wire with a power $P=I^2R$, ...

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The motion of electrons in the wires and the voltages can't be "seen" by naked eyes so the whole science of electric circuits is automatically "harder to visualize" than mechanics. But all such laws and phenomena have mathematically similar analogies in mechanics. The voltage is analogous – not only mathematically but physically – to the slope of an ...

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With static electricity, the electrons cannot move because the material used is an insulator. Hence there is no current. If the material were conductive, then a current would flow, and there would be no accumulation of charge. Electromagnetic fields will induce a voltage in a conductor, so there will be a current as well. You also need to remember that ...

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Fundamental particles like the electron are well-known to have magnetic dipole moments related to their spins. Moreover, the standard model also predicts that they should have small electric dipole moments (EDMs) as well. However, the EDMs predicted in the standard model are very small; they will probably be too small to observe directly for quite some ...

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It is like water in a hose. If the hose is full of water, water flows out the end immediately when you turn on the faucet. A drop of water at the faucet pushes a drop next to it, which pushes the next drop. Water doesn't flow that fast. If the hose is empty, it takes a while to reach the end.

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Often the easiest way to do such problems is using potential rather than the electric field. And always, it is best to use the appropriate coordinates. In this case, cylindrical coordinates with the rod at $\rho=0$ and extending from $z=-L/2$ to $z=+L/2$ are natural. So what you do is say that for an element of rod with a tiny length $d\ell$ and charge $\... 1 Your reasoning is faulty. It is true that in electro-STATICS (ie when there is no movement of electric charges) the electric field inside a conductor is zero. But this is not the case for electro-DYNAMICS (ie when charges are in motion), eg when there is an electrical current flowing. It is also true that, for alternating currents, the current becomes ... 1 An electron gun is used to shoot electrons at the ink which then gives the ink droplets a negative charge, varying based on where the ink needs to go. Then, the charged ink droplet passes between two metal plates, which deflect the ink to its appropriate location on the paper. The ink does not acquire charge from the metal plates, but from the electron gun. ... 1 All of the AC motors will create a "back pressure" once power has been removed. I do however not believe you when you say you have a properly grounded piece of equipment. Please note...the grounding system must be complete ALL The way back to a earth ground (grounding rod ect)...grounding cables can have a tendency to create a thin film of oxidation on ... 1 It depends on what you have. Sources can be modeled as a current source or a voltage source. If you treat it as a voltage source, it will always output that peak voltage and the circuit current will change according to the resistance changes. If you treat it as a current source, it will always output that peak current and the voltage drop across it will ... 1 In the series connection the current (charge passing a point per second) is the same every where because there are assumed to be no sources or sinks of charge and so the charge is conserved - the amount of charge entering is equal to the amount of charge leaving. This is Kirchhoff's current law and there is certainly no accumulation of charge rather the ... 1 The traditional electric bell uses an electromagnet to move the arm that strikes the bell. Electromagnets require the core to be low coercivity as a high coercivity causes losses due to hysterisis, and iron happens to meet this requirement. There is nice explanation of the effect of coercivity in the answers to Properties to select suitable materials for ... 1 The solution to this interesting question has to involve both (a) the distortion of the electric field of point charges when they move close to the speed of light and (b) time (since the longer we wait the further apart the electrons become, so their mutual force becomes smaller). Since the electrons are moving along the same straight line we can reduce ... 1 Long ago somebody decided that the direction of "conventional" current flow was the same direction as the direction of flow of positive charges. In that convention the flow of negative charge in one direction is equivalent to the flow of positive charge (and hence the conventional current) in the opposite direction. When introduced electricity usually ... 1 At the cathode the reaction is: $$ne + X^{n+} \rightarrow X$$ where$X^{n+}$could be$Cu^{2+}$or$H^+$. The$Cu^{2+}$comes from the copper sulphate dissolved in the water and the$H^+$comes from the dissociation of the water: $$H_2O \rightarrow H^+ + OH^{-}$$ The equilibrium constant for the above reaction is$10^{-14}$for pure water at room ... 1 Maybe a slight easier to follow answer, based on the Quora Website The permittivity of free space is a number which allows us to describe how easily (or how difficult) it is for electric lines of force to pass through air, water or any other medium. It's called permittivity because of how much a given substance "permits" electric, (or magnetic in the ... 1 It comes from Coulomb's electrostatic law: $$F = \frac{1}{4\,\pi\,\epsilon_0}\,\frac{q_1\,q_2}{r^2}$$ for the force between two charges$q_1,\,q_2$spaced by a distance$r$. So then$(4\,\pi\,\epsilon_0)^{-1}$is simply the force between two charges of one coulomb each spaced at a distance of 1 meter. The${\rm C^2}\$ in the unit definition means that if ...

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In simple terms it is a matter of scale. The sort of demonstration you see in laboratories have induced emf of a few volts and currents of a few milliamperes. The resistances involved are relatively small compared with those in electrostatic. When static electricity demonstrations are done, for example with the rubbing of glass with fur, the voltages ...

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It just refers to charge and there is no significant difference

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The power consumed by your circuit determines how fast the battery drains. P = I * E: power (Watts) is found by multiplying the current (Amps) by the voltage (Volts). Since your battery has a (reasonably) constant voltage under normal operation, current is the variable here. I = E / R, amps = volts / ohms. If we combine these two equations, we get P = E ^ ...

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