Confusing Electricity: Uncovering the Mysteries of Voltage and Resistance

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    Confusing Electricity
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Discussion Overview

The discussion revolves around the concepts of voltage and resistance, particularly in the context of stun guns and the behavior of resistors in circuits. Participants explore the implications of high voltage and low current, as well as the effects of adding resistors in series and parallel configurations.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant notes the confusion regarding how a high voltage stun gun does not produce high currents, suggesting that the voltage rating is between the prongs and that the electricity travels only a short distance.
  • Another participant proposes that the specified voltage of stun guns may be the unloaded value, implying that the actual current could be minimal due to the limited charge available.
  • A participant corrects their earlier statement about resistors, clarifying that adding resistors in parallel decreases total resistance, which allows more current to flow.
  • One participant explains that stun guns have capacitors that hold little charge, leading to a rapid drop in voltage, which is why they are generally not lethal.
  • Another participant questions the idea that the current would remain constant, suggesting that the voltage drops sharply after the initial discharge.
  • A participant compares the situation to static electricity, noting that high voltage can occur without lethal consequences due to the small amount of charge involved.

Areas of Agreement / Disagreement

Participants express various viewpoints regarding the behavior of stun guns and resistors, with some agreeing on the role of capacitors and the nature of voltage drops, while others remain uncertain about the implications of these concepts. No consensus is reached on the overall understanding of the issues discussed.

Contextual Notes

There are unresolved assumptions regarding the behavior of voltage and current in stun guns, as well as the effects of adding resistors in different configurations. The discussion reflects a mix of technical reasoning and personal interpretations.

Krb686
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Well I guess it's pretty simple, I know E = IR, but I've been thinking of some situations lately that have been confusing me so I decided to ask here. The first one is how does a high voltage stun gun not create high currents? The highest I've seen is 4.5 million volts. I think they simply can't kill you because it is 4.5 million volts rated between the two prongs so the electricity only travels an inch or two correct? My finger reads 7 million Ohms over an inch, which would mean if I stuck that stun gun there it would create .65 Amps right?

The second questions is since when you add resistors in series, the total resistance drops, why couldn't you just keep adding resistors until you have an extremely low resistance and create high currents off of low voltages? And how does it make sense that adding more resistors drops overall resistance anyways?
 
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Dunno from stun-guns. Maybe the spec'd voltage is the un-loaded, before you unload on someone's butt, value. There could be just a few electrons even at 4.5MV, so the current would be minimal.

But to the resistors. Firstly, resistors in _parallel_ decrease the total resistance. You can imagine it as increasing the number of paths for current to flow. As you keep adding resistors, more current flows. However you are not "creating" current flow. The voltage (think of it as pressure) is creating the flow, and the source will always have a limit on how much it can push. As you approach that limit the voltage will begin to drop, or your resistors will melt, whichever happens first.
 
Okay that makes sense now, sorry I mistyped that I meant to say in parallel.
 
I don't get where the confusing part is.

The stun guns have capacitors which hold very little charge, its not an infinite power source so the V drops exponentially. It would start at 650mA or whatever you got, but drop very quickly, that's why it won't kill you (most likely).

I heard of cases where stun guns killed, but maybe its the police brutality propaganda or what not.
 
Curl said:
I don't get where the confusing part is.

The stun guns have capacitors which hold very little charge, its not an infinite power source so the V drops exponentially. It would start at 650mA or whatever you got, but drop very quickly, that's why it won't kill you (most likely).

I heard of cases where stun guns killed, but maybe its the police brutality propaganda or what not.

What do you mean it would drop? I thought it would just carry 650 milliamps constantly through wherever on your body it was touching.
 
lololol no no no no. Its not an ideal voltage source. The 4.5 million volts is for an instant, and drops sharply.

When you rub your cat with a balloon you have a potential of about 10 million volts or so on the balloon, but it never kills you. The amount of CHARGE is very small (learn about charge, unit is coulomb) and the energy is small also.
 

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