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Quote from: jccc on 02/08/2014 15:33:59Unit charge is electron and proton, what is energy? Charge potential? 1/2mv^2? How's energy or charge relate to volt? Look 2 pages of discussing, what's the correct analogy? There is no useful analogy. The relationship between energy (measured in joules) and charge (measured in coulombs) is 1 joule per coulomb = 1 volt. That's it. Energy is the ability to do work: one joule will raise the temperature of a gram of water by about 0.24 degrees. One coulomb is the charge of about 6.2 x 10^18 protons. Measurement of charge is quite difficult but current (charge flowing past a point per unit time) is easy so we generally measure amperes (1 amp = 1 coulomb per second). Now consider an electric kettle running at 240 volts, 5 amps. 240 x 5 = 1200 joules per second so it will heat 1 gram of water at 0.24 x 1200 = 288 degrees/second, or more realistically 1 liter (1 kg) at 0.288 deg/s, say 4 minutes to boiling. It's important not to get too hooked on to electrons when dealing with current electricity: the current in aluminium and many semiconductors is due to the movement of positively charged "holes" (see the Hall effect for an explanation of how we know this) and in liquids or gases, by the movement of ions with both positive and negative charges. But the definition remains the same: 1 volt = 1 joule per coulomb.
Unit charge is electron and proton, what is energy? Charge potential? 1/2mv^2? How's energy or charge relate to volt? Look 2 pages of discussing, what's the correct analogy?
A classic capacitor has two flat conductive plates (electrodes)...
There are many different kinds of capacitors, one not really deserving the name classic over the other.