Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [current]

Flow of electric charge - typically movement of charge carriers, such as electrons. Measured in amperes (A).

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What are Guard Rings?

I have heard about Guard Rings many times, and I know they are supposed to avoid currents in places where there shouldn't be no currents, but I never found a good text to read more about it. Can someone describe them properly or please recommend…
mFeinstein
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Why does a body submerged in a more conductive fluid still conduct current?

Let's take for example an electric eel applying an electric shock by creating a potential difference across two points in the water. It would seem, however, that the current would find a "shorter path" across the potential difference by just…
CaptainCodeman
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Was Benjamin Franklin wrong (about conventional current)?

I am starting to see a lot of people claiming that convential current is 'wrong' because Franklin made an error when he first started investigating electrostatics, and that later scientists didn't bother correcting the mistake, but preferred to keep…
Myforwik
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How exactly does a series voltage divider work?

I apologize if this comes down to a lack of fundamental understanding of electrical flow, which it probably does. When I look at this: I don't understand why Z2 is factored into Vout - as far as I can tell the current should branch out before…
J S
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Does electricity go from negative to positive or vice versa?

It's common knowledge that electrons flow from negative to positive, but I have noticed than often the direction of the current is ignored. For example, the resistor is often put AFTER the LED, or the diode is put the opposite way. Why is the…
user7776
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Can I using nichrome wire to light a candle electronicaly?

I want to be able to create a set of candles that light automatically (for a presentation) however it's almost 100 candles and I need an inexpensive solution. I know that nichrome wire get's hot when you pass current through it but can it get hot…
user3045
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electric chewing gum prank circuit diagram

I'm new to electronics. I'm trying to find out how this works out of curiosity. http://www.amazon.com/gp/aw/d/B0050UNNQS Does anyone have a circuit diagram for the circuit? Is the current safe for such a prank? Internal picture: EDIT: Merged…
quwuwuza
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2.15GA Current?

I'm using this app called iCircuit for Android (I'm asking here because the iCurcuit forum has been forsaken) and when I have a circuit with a 3V battery and an LED, it lists the current as 2.15GA. I'm new to electronics so I'm wondering why its…
MichaelK
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How to reduce current?

Let's say I have a power source of 4.2V/1A. I know how to reduce the voltage using resistors, but if I would like to be able to 'divide' current in half for example, how can I do that using standard components? My component is a battery, which…
0x29a
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Contactless detection of AC currents?

I like to detect current passing through a wire. I have only a very small opening (15-20mm diameter) that access to wire so using a current transformer is not feasible. I can touch the bare wire. (I can touch with a tip of a scope probe) The wire…
Ktc
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How does a power surge reset a modem?

Yesterday, there was a huge power surge in my area, and I wasn't able to connect to the internet any more. The reason was that the Wifi modem was somehow automatically reset to its factory configuration. I had to reset it to my settings today to get…
Lazer
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Is conventional flow a real, physical thing or is it something we made up?

Is conventional flow a real, physical thing or is it something we still use for historical reasons? • Electron flow is the actual current flow and the textbooks are the other way because of Benjamin Franklin. • Conventional current is real and…
Sam Pan
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Calculate the maximum current of zero ohm resistors

According to Ohm's Law, if the resistance is zero, the power dissipated by a resistor is unmeaning. $$P_d = R \times I^2$$ $$I = \sqrt{ \frac {P_d}{R} }$$ Can one calculate the resistance given that power is defined? Only by knowing power, how can…
musefian
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How to supply power from vehicle to a low power device?

I am a programmer with only basic understanding of electronics/electricity. I am trying to install this device into my vehicle. The device accepts a wide DC power input (10V to 30V), but has a maximum power supply rating of 12W (Edit: had typed…
HRJ
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AC, DC, what else?

Aside from alternating current and direct current we already know, do you still other type of current flow? Also, is it for that type of current flow to exist? or there are only 2 types of current flow in this universe (ac,dc)
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