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Questions tagged [electricity]

The study of the presence and flow of electric charge. Charges, currents, fields, potentials.

Usage Guideline

Use this tag for any question related to electricity.

Description

Electricity is the set of physical phenomena associated with the presence and motion of matter that has a property of electric charge.

Learn More

You can learn more about electricity and related phenomena in Wikipedia.

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Why does public mains power use 50-60 Hz and 100-240 V?

Is there a physical reason behind the frequency and voltage in the mains electricity? I do not want to know why exactly a certain value was chosen; I am rather interested to know why that range/order of magnitude was selected. I.e., why 50 Hz and…
SuperCiocia
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Why is the charge naming convention wrong?

I recently came to know about the Conventional Current vs. Electron Flow issue. Doing some search I found that the reason for this is that Benjamin Franklin made a mistake when naming positive and negative charges. There is even this little comic…
GetFree
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Does electricity flow on the surface of a wire or in the interior?

I was having a conversation with my father and father-in-law, both of whom are in electric related work, and we came to a point where none of us knew how to proceed. I was under the impression that electricity travels on the surface while they…
N. Owad
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What is "Induced Atmospheric Vibration"?

The blackout seen today on the Iberian Peninsula has been attributed to a "rare" phenomenon known as "induced atmospheric vibration": It says that "due to extreme temperature variations in the interior or Spain, there were anomalous oscillations in…
tobalt
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Why do grapes in a microwave oven produce plasma?

Some of you may know this experiment (Grape + Microwave oven = Plasma video link): take a grape that you almost split in two parts, letting just a tiny piece of skin making a link between each half-part. put that in a microwave oven, and few…
JBE
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Why do power lines buzz?

When near high tension power lines, particularly after a good rain, the lines themselves emit a buzzing noise. A similar noise can be heard coming out of the electric meters attached to my apartment. I've heard before that this is supposedly from…
Billy ONeal
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In what order would light bulbs in series light up when you close a long circuit?

For a few days, I was thinking of this question. Lets assume we have a simple circuit that is 100 meters long. And lets say that we have bulbs A, B and C connected to the circuit's 30th, 60th and 90th meter relatively (from the + side). When we…
Huzo
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If water is not a good conductor, why are we advised to avoid water near electricity (no wet hands near circuits etc.)?

How can water be a medium to conduct current while its ionisation is so negligible that, in principle, no current should flow?
Muhammad Hashim
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Why do we use AC for long distance transmission?

Why do we use AC (Alternating Current) for long distance transmission of electrical power? I know that AC is such a current that changes polarity (magnitude and direction) and has fixed poles.
EiNsTeIn
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Why don't electric fish shock themselves?

Fish like electric eels and torpedoes have specially designed nerve cells that allow them to discharge hundreds of volts of electricity. Now, while pure water is usually nonconductive, the dissolved salts and other stuff in both sea and fresh water…
user172
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Why is there no magnetic field around a wire connected to electricity at home?

Is it true that an electric current that flows through a conductor creates a magnetic field around the conductor? If yes, then why doesn't the magnetic sensor of my mobile device react in any way to changes when I bring the device near to the wire…
Turkhan Badalov
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How did physicists know that there are two kind of charges?

Problems The question I am about to make is either too stupid or hasn't bothered anyone because its obvious because I can't really find the answer anywhere. I am currently studying electricity and magnetism and my book starts by telling that matter…
George Smyridis
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Why is AC more "dangerous" than DC?

After going through several forums, I became more confused whether it is DC or AC that is more dangerous. In my text book, it is written that the peak value of AC is greater than that of DC, which is why it tends to be dangerous. Some people in…
Four Seasons
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Difference between live and neutral wires

In domestic electrical circuits, there are 3 wires - live, earth and neutral. What is the difference between the live and neutral wires? As there is AC supply, it means that there are no fixed positive and negative terminals. Current rapidly…
ghosts_in_the_code
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Does alternating current (AC) require a complete circuit?

This popular question about "whether an AC circuit with one end grounded to Earth and the other end grounded to Mars would work (ignoring resistance/inductance of the wire)" was recently asked on the Electronics SE. (Picture edited from the one in…
BlueRaja - Danny Pflughoeft
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