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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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What causes electrical boxes to hum?

Often times you pass by an electrical box on an electrical pole and you hear a distinct hum emanating from it. What causes that tone? Does the flow of electricity itself have a sound? Or does the flow rattle the metal parts at a certain frequency,…
user151841
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Static electricity and door handles

I have a pair of shoes, which seem to isolate me from the ground. In effect I'm gathering static charge and every time i grab an aluminum door handle, that current discharges and that hurts. Ouch. I invented a way to workaround that: when I'm going…
Spook
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Why does my wife's skin buzz when she's using her laptop?

When my wife uses her laptop, if I touch her skin, I can feel a buzz. She doesn't feel the buzz, but she can hear it if I touch her ear. So I'm guessing it's a faulty laptop, and she's conducting an electrical current. But why would she not feel…
Tim Gradwell
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What are all the lines on a double circuit tower?

I understand what three-phase power is. But when I look at some pictures of a double-circuit-three-phase-power-line I see two or three lines close together? What is the purpose of these lines close together? (the wires are attached by smaller…
jpell
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Why can different batteries with the same voltage send different currents through the same object?

According to an answer in this thread on Skeptics: If you take one of the little 12V garage door opener batteries and short out (directly connect) the two terminals with a piece of wire or something else. You'll get a light current flow…
Casebash
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Does A.C. make the material through which it is flowing vibrate?

So recently I have been studying A.C. circuits and the graphs show that the current oscillates itself as a function of time. Now, according to me an oscillating body vibrates. Hence, the oscillating electric current should also make the medium…
Vaibhav Singh
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Why is electric current dangerous to humans?

How does a strong electric current harm our body? A strong electric current will posses a great charge. But how does that charge injure us?
Harry
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How much of current flows through a bird sitting on a power line?

I've been googling for hours and went through over a hundred answers. Now, some say the bird doesn't form a closed loop, some say the current is so small that it doesn't kill the bird. From as much as I understand electricity, I'm sure the bird does…
Dalius
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Why are electric shocks felt asymmetrically?

I have been zapping people quite a lot recently (e.g. when shaking hands), probably due to new shoes. What I noticed is that usually I can't actually feel the shock, even though the other person quite clearly can. Why are static electric shocks from…
Wolpertinger
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What is electric energy since electrons are not consumed?

I am interested in electronics as a hobby, so I have been reading up on the physics of electricity. I understand that difference in charge on battery terminals causes electrons to flow naturally through a circuit. (Like an object in a gravitational…
skibulk
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Why do electric shocks send you flying?

One question which has recently been interesting me is: Why exactly do people get thrown back when they are shocked by electricity. I have done some research to find the answer to this, and I am yet to find an answer. My personal and initial…
user4493605
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When we get an electrical shock, the ciruit is incomplete but still the current flows, why?

If we touch the live wire and ground at the same time, we will get a shock. But the current goes from live to ground and not to neutral i.e, circuit is open. Then how can we get a shock? This is the same circuit: will the current flow? I think…
Kartik
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How do test lights (mains tester) work?

I was wondering how one-contact test lights work. Obviously there is a small current running from an energized pole through the human body somewhere that is still large enough to produce a visible light. German wikipedia talks about the current…
John
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A circuit with no voltage difference, but current flowing

From Michael on Skeptics Stackexchange: How about a wire that's grounded? Safe to touch, right? WRONG. ________________ 30 amps -> ________________ | | + …
Casebash
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Salt water conduction

Does salt water conduct mostly by the ions travelling through the solution, or by electrons collectively flowing or hopping through the solution like in metals?
Ginsberg
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