Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [electricity]

For EE.SE purposes, the creation (battery/generator/solar cells), storage, control and transmission of electrons. This can be broken down into sub-topics such as voltage, current, reactance and ohms. These can be broken down into more sub-topics such as electromagnets, coronas, heat, ESR, EMF. This excerpt just touches on all the endless fields electrons are involved in, including physics.

387 questions
38
votes
4 answers

Why can the regenerative brakes of the Oslo Metro only share energy with other trains if they are "nearby"?

I read on Wikipedia that the Oslo Metro has regenerative braking, but no batteries to store the energy. Therefore, the energy can only be utilized if there is another train "nearby" to utilize the energy. How far is "nearby"? Due to the bottleneck…
Fiksdal
  • 942
  • 2
  • 9
  • 18
18
votes
5 answers

Why do computer graphic cards use 8 pin (4 positive and 4 negative wires) connector instead of connector with only single positive and negative wire?

I've always wondered why computer graphic cards use an 8 pin (4 positive and 4 negative wires) connector instead of a connector with only a single positive and negative wire.
loki floki
  • 205
  • 2
  • 3
16
votes
8 answers

Why are circuits considered loops?

So, I know that when you're talking about something like a circuit that includes a battery, a circuit LOOKS like a loop, but that's merely because of the fact that the power supply is physically close to the output. However, this doesn't have to be…
dudewad
  • 265
  • 2
  • 7
14
votes
5 answers

Does coiling and straightening a wire change its resistance?

I’m looking to make my own kiln coils and I wanted to know why are the coils coiled? When the coils are stretched too far apart they run cold and when they are close together they run hot. What is the reason for this if resistance doesn’t change…
Wes
  • 269
  • 2
  • 6
5
votes
3 answers

how does this occupancy-sensor switch not need neutral?

Note, I don't think this belongs in DIY; it's a bit more complicated than that. I bought a Lutron Maestro occupancy sensor switch, and was perplexed to learn that it doesn't need a neutral in the switch box (they brag about this as a feature, and…
RustyShackleford
  • 351
  • 3
  • 14
4
votes
3 answers

Would additional low voltage DC sockets be practical on mass scale?

In RL I noticed that power supply cables with possibility to charge one mobile through USB compatible socket actually exist: I actually started to wonder, whether for purpose of world building such idea could be move much more further. I mean both…
Shadow1024
  • 151
  • 3
3
votes
1 answer

How does peer-to-peer energy trading work?

I am relatively new to the topic, with not the greatest electrical engineering background, so these questions may sound simple, but I still cannot figure out how certain platforms such as piclo, vandebron and others manage to trade electricity…
dsax7
  • 193
  • 7
3
votes
4 answers

How can cellphones be charged and used at the same time?

All of us are probably used to using our phones while they are charging. This is why manufacturers make longer cables – so that the consumer can have the facility of using and charging the question at the same time. My question is this: Assuming a…
Anurag Baundwal
  • 135
  • 9
3
votes
1 answer

Why does it matter which way I put a battery into an electronic device?

If I take a battery, some wire, and a light bulb and hook them all in a circuit that would create a current and light the bulb. If I turned the battery around so the terminals were switched then I would have a current in the opposite direction, but…
Nova
2
votes
4 answers

Earth potential and grounding

Electrician apprentice here. Earth potential is said to be 0 volts. Let’s say I have a star-configured transformer which supplies me with voltage. Let’s also say that the transformer is perfectly balanced and that the 0 potential center point is…
David
  • 21
  • 1
2
votes
1 answer

Measuring resistivity of dielectric liquid

Is it possible to reliably determine the resistivity of a highly resistive liquid above the breakdown voltage (i.e. after ionising the substance)?
J. Doe
  • 97
  • 1
  • 9
2
votes
1 answer

Electrical circuit with capacitors and transistor

I don't know how this circuit works. So I would like someone to explain me. I know that the qustion is too general, but I am new in electricity and I don't know someone who can answer me how this works. The result is that when The circuit is…
DPM
  • 123
  • 4
2
votes
6 answers

How do electrons carry energy

So when electrons leave the negative side of the battery and the voltage get lost across the resistors in the circuit ..how do the electrons lose their energy ? How do the electrons carry that energy that produces the electricity then they LOSE it…
user8700093
  • 37
  • 1
  • 1
  • 2
1
vote
0 answers

Choosing the right power-switch with LED for a simple electrical design

I want to add an ON/OFF switch with an integrated indicator LED to a very simple electronic design, between a 9v battery and the connected module that it powers. What should I be looking at to select the power switch ( specifications ) and can I…
Sam
  • 13
  • 4
1
vote
3 answers

Static Electricity Accumulation

I don't know much about electricity. I live in an old building experiencing bizarre electric phenomenon. The building might have bad wiring, I live near elevators and power distribution for the entire building in a large multi-floor building. I hear…
cascol33
  • 23
  • 1
  • 1
  • 5
1
2 3 4 5