Electricity is the set of physical phenomena associated with the presence and motion of matter that has a property of electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwell's equations. Various common phenomena are related to electricity, including lightning, static electricity, electric heating, electric discharges and many others.
The presence of an electric charge, which can be either positive or negative, produces an electric field. The movement of electric charges is an electric current and produces a magnetic field.
When a charge is placed in a location with a non-zero electric field, a force will act on it. The magnitude of this force is given by Coulomb's law. If the charge moves, the electric field would be doing work on the electric charge. Thus we can speak of electric potential at a certain point in space, which is equal to the work done by an external agent in carrying a unit of positive charge from an arbitrarily chosen reference point to that point without any acceleration and is typically measured in volts.
Electricity is at the heart of many modern technologies, being used for:
Electric power where electric current is used to energise equipment;
Electronics which deals with electrical circuits that involve active electrical components such as vacuum tubes, transistors, diodes and integrated circuits, and associated passive interconnection technologies.Electrical phenomena have been studied since antiquity, though progress in theoretical understanding remained slow until the seventeenth and eighteenth centuries. The theory of electromagnetism was developed in the 19th century, and by the end of that century electricity was being put to industrial and residential use by electrical engineers. The rapid expansion in electrical technology at this time transformed industry and society, becoming a driving force for the Second Industrial Revolution. Electricity's extraordinary versatility means it can be put to an almost limitless set of applications which include transport, heating, lighting, communications, and computation. Electrical power is now the backbone of modern industrial society.
Information (dielectric constant, loss tangent, temperature ratings, etc.) about all insulating materials of interest to EE's from resins to wire insulations to circuit board materials. Condition is very good, with no markings except for a name stamp on the flyleaf. The only condition issue is...
Hello everyone, I am very new to physics, I'll leave that at that for now. However I came here because I am in the process of coming up with a build for my own generator and honestly I loved electrical engineering just didn't have the ability to pursue it. Now I have been brainstorming and am...
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OK This is BOGGLING my mind. How is it even possible? I am trying to figure it out before I look in the Jboxes of the lights.
Any ideas?
Newly installed recessed lights done by skilled electrician.
One switch controls all lights.
SWITCH goes ON: One light off rest of lights...
Hi everyone here.
In 2012 when i was 22 years old , i started an apprenticeship in electronics repair , and worked for my self for almost 5 years .
I was repairing switching devices like welders and inverters , easy job by replacing bad components like IGBTs and capacitors.
In 2017 i started...
Hello everyone, I've recently found myself missing the days of php based internet forums, long-text formats with a good culture and personality.
It sounds ridiculously corny to make personal introductions as a newcomer but I guess it's a breath of fresh air to have to write one in today's very...
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So I am making a Ni-Mh battery , and for space constraints, I need to put 2 batteries in paralell + 1 battery in series with them.
So if I get two batteries of 2100 mah in paralell I get 4200 mah, but if I put them in series with one 2100 mah battery , what would be the...
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I am looking into electrical engineering because I think it is an awesome major because of the math and physics involved. I am not really into building things though. I love software and computer science-related things, but I do not want to major in CS because it is a very popular major...
I’ve recently restored a Cossor 501 valve (tube) radio, which can receive LW, MW and SW. It has an external antenna socket (for SW), and I’d like to gain some knowledge on how to design and build something to plug in to it.
A single wire about 20m long, draped out of the window, has enabled me...
Hello, I'm a retired professional, electrical engineer now writing and publishing science fiction novels, both with good---seems to me---Kirkus Reviews. My stories are based upon my own speculative (fantasy?) physics, and otherwise hope to be realistic. I need help with details from physics...
Hello! I am an electrical engineer from South Korea. While studying at university, I developed a late interest in physics through learning Maxwell's equations. I've come here to participate in meaningful discussions. Thank you :smile:
I've been reading about how color crt displays work because I've become interested in trying to make one, even if it isn't going to be very good compared to the ones of the past. (yes I know they have high voltage that can arc through material/ air and that voltage drop and electron collisions...
M.S in electrical engineering, Has a publication on IEEE titled “New Concept About Common Mode Noise”. I have extensive knowledge in electrical engineering, including quantum.
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We need 20 meters of 12 Gauge electrical wire but don't have 12 Gauge wire. Can we use two 6 Gauge wires and twist the two ends of the wire together? Is it harmful to electronic appliances? for example, air conditioners
[Mentor Note: original question restored; the OP will post a follow...
I'm an electrical engineer of 35 years. I've been in multiple industries, but now work with satellites, LEO specifically. I'm also a Ham Radio operator, AC7DN.
My favorite quote is from Leonardo daVinci - "Simplicity is the ultimate sophistication."
I'm an electrical engineer working in the medical device industry.
As a hobby, always interested in both physics and metaphysics, want to know what this world is about at its core. Always open to any seriously and honestly driven discussion as long as it is not offending and has the goal of...
I have trouble researching whether valence-electrons take part in electrical conductivity. Some sources say that a lower amount of valence electrons lead to an higher electrical conductivity, whilst others say the opposite. And each have their different reasons, for example, lower valence...
TL;DR Summary: Just need help with verification of data submitte
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Efficiency distance over 3000 km +, plus Temperature over that distance
1-inch amorphous magnetic core
0.05 microns graphene
0.10 microns metallic PZT
Helical copper wire with 15 mm...
I've recently graduated from EE and was looking for jobs on the market. While I'm looking for any good opportunity that comes my way, I wanted to plan out my career path and how to achieve it in the long-term. That way, when I run into roadblocks and issues on the job, I'll be able to think...
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I am trying to get to an answer for the following scenario.
Imagine you have an electrochemical cell in its most basic terms.
On the negative electrode you have 3 moles of iron metal in a chloride solution. On the positive side you have 3 moles FeCl3 solution. These are separated by a...
Is there a way to know what is the amount of energy a wire can transport and know what is the amount of energy transported by moving air at a certain psi.
I was wondering if the electrical force, which is a radial force that depends on the inverse of the distance squared, also respect the Three Kepler Laws?
If so, what will the constant for the third law be?
Hi all,
I just read this article about how electrical transformers work and have some questions.
https://www.dfliq.net/blog/the-basics-of-electrical-transformers/#:~:text=The%20three%20important%20components%20of,magnetic%20flux%20is%20initially%20produced.
i). What exactly is magnetic...
My name is Joe,
I'm 36 years old and currently between work. I live in The city of Erie, Pennsylvania.
My interests are in the phields of electricity, physics, chemistry, and all engineering principles related. As I am only a high school graduate with no formal training, my education is self...
Hi Physics folks,I am currently collecting resources for my senior seminar project at my university and would like to ask if anyone has any good references for gold thin films. I am planning on focusing primarily on the electrical and optical properties of gold thin films. I appreciate any...
Hi everyone, I'm new here but I've come across PF many times as viewer while searching for clarifications and exercise solutions.
I think this should be the right place to ask for advice.
My background: 30-ish years old, got my BSc and MS in Electrical Engineering in 2017. The courses were...
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I recently bought a cabbing grinder machine from India and now recognize that the motor(1/2hp 230v~) doesn't have any safety label or certificate whatsoever.
I know close to nothing about motors or electricity and ask myself if it is safe to use the machine. To be honest I don't even...
I am currently in my final year of high school in India, and slightly confused as to which course I should take. I've always been interested in physics, and would eventually like to do research in quantum computing. I'm not sure whether to take a B.S. in Physics, or engineering (a BTech) in...
I do not mean neutral electrical charge, but a forth kind (if exists)
I am in 9th grade, and someone asked the teacher if there is an electrical charge that is not positive, not negative and not neutral, maybe something in the middle of them.
The teacher said that there is a charge like that...
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I've conducted an experiment to work out the efficiency of a small motor, and it comes out to be very low. Have I done my calculations correctly?
I connected the motor to a gearbox (made from Meccano) and a winch and used it to lift a weight. I measured the DC voltage across the...
This is less of a nuclear physics question and more of an EE one, but I think this is the right place for it.
There is a startup called Zap Energy and their approach to fusion is to create a inertial confinement pinch with an electrical discharge.
This is a bit similar to what the Sandia labs...
Electrons flowing through a resistor are dissipating electrical energy. The electrical energy is transported from the battery to the electrons along the curved field lines of the Poynting vector. It seems like a meaningful idea that electrical energy necessarily travels from the source to the...
Summary: Trying to self-teach Electrical Engineering, Embedded Linux and AVR/ARM to make a career change into embedded systems development and I need suggestions on the best way to do that. I have a plan but I honestly have no idea if its a good one.
I have been into computers my whole life...
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I'm trying to decide between physics and electrical engineering. I like building electrical stuff, and I like solving physics problems, but my main goal is to try to build power systems that integrate things like what can be found in this paper https://arxiv.org/abs/1401.0520. I would...
I understand that electrical conductivity is a measure of how easily charges are able to move in an object.
During charging by conduction (for conductors), it seems that we simply have to add the charges of both object together and divide by two to obtain the resultant charge of either object...
I am new here and I am seeking for help:) Thank you so much.
In engineering, electrical formula often analogy to mechanical formula.
eg. power[W] = pressure x volume flow rate vs power[W] = voltage x current
My question is could we make the simplest unit between electrical and mechanical...
What I have done:
(1) ##I(0)=\frac{V}{R}=\frac{1.5}{25}A=0.06 A.##
(2) By setting ##I(t*)=0.06(1-e^{-(35/0.4)t*})=35 mA## we get ##t*\approx 0.01 s##
What I have done seems correct to me, but the result for part (2) should be different.
I would be grateful if someone could point out to me...
The image i provided is a section of microcontroller circuit that i used to interface code in C with the I/O port of the microcontroller, in Proteus.
I have realized i was only ever told to learn how to measure the voltage and current across the components, Kirchhoff's rules and all, and...
Calculation of the potential electrical energy generation of a siphon pipe, emptying an enclosed reservoir and end of siphon pipe connected to a pelton turbine with efficiency of 75%
Known inputs:
Height difference of siphon(Hd) = 4,5m
Height lift of Siphon (Hu) = 6m
Total siphon pipe length...
I have in the past been criricised for inappropriate postings that I could have resolved with research so this time I have done the research first.
The best solution I have found is from wiki "that causes it to experience a force when placed in an electromagnetic field."
What causes the force...
Picture for better understanding.
My answer :
I want to know how to solve this problem without using cylindrical. I mean how can we solve this using cube and its sides.
Thanks.
Hello, all. First, I want to apologize if this is not the correct forum or area of the forum for this question. Please direct me if I should be posting this somewhere else.
I have some questions regarding what I believe is best described as the "theory" of electrical capacitance. As my...
What is the electrical resistivity of Caesium vapor? What is the electrical resistivity of Potassium vapor? Sorry there are no support material or reference links for this. Just a question. The unit must be in Ohm-meter.
The video on youtube on the above link seems to imply that electrons don't flow through a circuit. At 01:29 into the video, the narrator says that he used to teach his classes how electrons move through a circuit by using a clear plastic tube with a chain inside of the clear plastic tube. The...
Here are the details. I started with a nut and bolt, and drilled a hole down the center of it. I inverted and glued into place a carbon fiber rod in the hole. I glued a bit on the end of the bolt. I wrapped magnet wire around the bolt on each side of the rod 400 times. I made a commutator using...