Thanks for your response, Monolith.
OK, some of this is starting to come together. Between your reply, recent posts by evan9162 and others, and some research last month on fan speed controls, I may be starting to understand at least something.
Now I'm going to use quotes excessively...
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Voltage is "potential" that is measured relative to something (typically "ground"). Voltage is basically the difference in charge levels between these two references.
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Would it be a good analogy to say voltage is like the potential energy of a bowling ball up on a shelf in relation to the floor, and the higher the ball is could be seen as higher voltage?
And more to what you said (I hope I'm using the right terms here), does electrical potential have to do with how many of electrons a negatively charged atom has to give up to a positively charged one (or is it the other way around)?
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People often associate "ground" with zero voltage, but that is not necessary.
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Using the bowling ball analogy again, this would mean that the kitchen floor can be "ground" since it is lower than the shelf, but not necessarily having zero potential energy (there's still the basement)?
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Current is the flow of electrons (or holes - I won't debate this) from a higher potential to a lower potential.
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Does this mean that current is a product of voltage, sort of like how kinetic energy is created when potential energy is released?
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Current also produces electromagnetic fields as they flow. This is what makes an electric motor work (the fields interact with iron cores and electrically changes the iron core magnetic polarity to help spin the motor).
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Is this called inductance?
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"Resistance" (e.g., resistor, etc.) impedes current flow (current follows in the path of least resistance - that's why people get electrocuted).
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I guess resistance is like shoving a lot of water through a little pipe. When this happens with water, the result is high pressure (sort of like a loss of efficiency... takes a lot of energy to move water under high pressure as opposed to low pressure). With electricity, the result is heat.
Another water comparison is that it also takes the path of least resistance.
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A light bulb has a resistive element in it that glows when current is passed through it due to its resistance.
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This I knew... hey I'm good /ubbthreads/images/graemlins/wink.gif
So current is what produces physical work in an incan bulb, LED, electric motor, etc., not voltage?
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Resistors are also used to create "potential" drops to reduce voltage levels, but at the cost of reducing efficiency because power is given off as heat (due to the resistance).
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Does a resistor work by resisting current, or lowering voltage?
Is current limited only by way of reducing voltage, or not neccessarily?
And last question for now (I'll be amazed if people suffer through my rambling)...
I've heard it said that it's not voltage that's dangerous, but current. That's why a stun gun can be 50,000 V, but doesn't shove a lot of current so it doesn't kill ya'.
So back to the bowling ball. The potential energy (voltage) of it sitting on the shelf is not dangerous, it's the kinetic energy (current) of it falling on your head that's dangerous. Is this sort of the idea?
So, on a scale of 1 to 10, how am I doing?
I hate to learn everything by analogy here, but electricity is a mysterious thing to the newbie. I also don't expect someone to sit there and answer every single question I just asked. Hopefully though, this thread will gather enough questions and answers to benefit anyone who is confused by some of these concepts.