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According to "Surface chemistry of gold nanoparticles produced by laser ablation in aqueous media." Sylvestre J-P, Poulin S, Kabashin AV, Sacher E, Meunier M, Luong JHT http://pubs.acs.org/doi/pdf/10.1021/jp047134%2B A detailed chemical analysis showed that the nanoparticles formed were partially oxidized by the oxygen present in solution. The ...


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The voltage becomes the same as Earth, but this doesn't mean that the charge goes to "zero". By "zero" here, I mean that the positive charges (nuclei) are perfectly balanced by the negative charges (electrons). You can call the voltage of Earth 0 Volts, but this is a relative measure. Charge, in the usage here, is not a relative measure because it is a ...


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Your equations (1) and (2) are dimensionally equivalent. Take your equation (1): $$ F = BI\ell $$ The dimensions $I$ are $CT^{-1}$, so the right hand side are $[B]\,CT^{-1}L$ - I've left the dimensions of $B$ unspecified for now and just written them as $[B]$. Now take your equation (2): $$ F = BQv $$ which has the dimensions $[B]\,CLT^{-1}$. If we set ...


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Although Ampere's law and the Biot-Savart law are magnetostatic approximations, they will still approximately hold when the charge is moving slowly enough. The problem is you're just naively using an Ampere's law result derived for a steady current to a situation with a moving charge. Ampere's circuit law comes from $$ \nabla \times \vec{B} = \mu_0 ...


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What matters is the surface of the object (in this case sphere). On the sphere a charge would distribute uniformly. In the situation that you described what matters is the relative size of the surfaces of two spheres. Since they are equal the charge on both of the them is the same (and hence is the half of the original charge).


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the reason for enclosing the gold leaf in a container is simply that gold leaf is exceedingly delicate. The container protects the gold leaf from air currents that would otherwise move the gold leaves or even tear them. The exact nature of the container isn't important, and any container would work, though obviously we need it to be transparent so we can ...


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Quasi-neutrality is only observed with bulk plasma. Although it appears neutral to outside observance at large scales, we also know at smaller scales the movement of the charge carriers creates EM fields and electric currents which further affect its behavior. In reality in space no such condition exists, as the plasma is not confined in little glass jars ...


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There are broadly three classes of materials: conductor, semiconductor, insulator. The conductor contains a LOT of electrons per unit volume. If you were to charge it, you would add a few more electrons. How many? Let's take copper. It has roughly $8.5\cdot 10^{28}$ electrons per $m^3$. If you have a wire of radius $r$ the number of electrons scales with ...


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The evaportation rate is given by $${dM \over dt} \sim T$$ where $M$ is the amount of evaporated water and $t$ is the time. $T$ is the temperature of the water. However, $${dM \over dt} \sim Q$$ Where Q is the charge of the water, to prove my point, consider a lightning bolt impacting water. The water is split into hydrogen and oxygen through electrolysis. ...



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