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.
I have asked multiple electricians this very question and none of them had an answer. I am working on a project right now that hinges on the control of electrical temperature. This is my first post, thank you in advance.
Homework Statement
I don't understand the answer to part b
Homework Equations
n/a
The Attempt at a Solution
The solution guide skipped too many steps. How was this derived? If the 5th charge is in the middle, it will be equidistant (about ##\frac {b\sqrt {2}}{2}##) from each of the...
I've just learned that the conductivity of super conductors increases with decrease in temperature and it becomes infinite at absolute zero. But I thought that all motion ceases at absolute zero. So how can current flow in such conditions? And how can its resistance become zero as some...
Homework Statement
You have been hired by Brockovich Research and Consulting (BRC) to research a new water purification device that uses seeds from the Moringa Oleifera trees.1 A protein in the seed binds to impurities causing them to aggregate so that the clusters can be separated from the...
Homework Statement
Homework Equations
F=kqQ/D^2=Ma
E=kQ/D^2
D=vt?
The Attempt at a Solution
So far, I've been able to label the forces on each ship through superposition. But that is all I currently able to understand. I know that my end solution is a speed/velocity, but I am not sure how to...
Homework Statement
A capacitor connected to a battery initially holds a charge of +q on its positive plate and -q on its negative plate. The electric field between the plates is initially E. A dielectric material is then inserted that polarizes in such a way as to produce an electric field of...
Homework Statement
A positively charged wire is bent into a semicircle of radius R, as shown in the figure below.
The total charge on the semicircle is Q . However, the charge per unit length along the semicircle is non-uniform and given by λ=λocos(θ)
What is the relationship between λo, R...
Homework Statement
Hello,I've always been told at school that conductors have resistance, and that resistance causes energy loss when current is flowing through the conductor, but I've never known the explanation behind that resistance.
Reading a little bit online, I saw 2 explanations:
1...
Homework Statement
You are studying Gossamer Spiders in a biology research lab and marvel at their ballooning stunts. These Spiders disperse by spinning strands of silk in open air. The flight of these spiders is electrostatic in nature because everything that moves through air develops static...
Homework Statement
In inkjet printing, a rapidly moving nozzle horizontally squirts drops of ink that form letters and images on paper. A common problem is horizontal white lines running through the print due to a clogged nozzle. Another common problem is paper dust.
(a) Within the context of...
Is it possible to vibrate a string with electricity? I'm guessing an electro-magnet placed close to the string would be able to vibrate it.
If the electro-magnet is used to vibrate the string, I'm guessing the electro-magnet should be pulsed at the fundamental resonate frequency of the string...
Hello,
I work with Particle Systems for special effects (Houdini FX) and I would like to build a electric arc system.
I can offset the positions of every particle by certain rules/conditions or expressions and maybe someone here,
Knows a expression or a good link to something like this. Some...
Homework Statement
I've attached a url with a picture of the problem setup and diagram
https://instagram.com/p/7nYNXTscre/
Homework Equations
I used the equation V = KΣiqi/ri to solve for potential at A and B
The Attempt at a Solution
For Va I used K((Q/d)+ (2Q/(d^2+d^2)^.5))
I just plugged...
Hello everyone. Hopefully someone would be able to help me with this problem.
The question states:
Two point charges qa = -12 micro coulombs and qb = 45.0 micro coulombs and a third particle with unknown charge qc are located on the x axis. The particle qa is at the origin placed so that each...
I had a question.
If a glass rod, with a charge of 5.4x108 C touched another insulator so that all of the excess electrons are shared equally. What would the final charge on the rod be?
I don't understand how to reach the answer of 2.7 x108 C.
Thanks in advance. :)
Homework Statement
How can I get the maximum Current Intensity by connecting 72 cells to a 3 Ohm resistor each cell has a potential difference of 1.5 Volt and internal resistance of 1 Ohm
Please don't tell me to connect them all in parallel or all in series as in parallel the potential...
Hi, I just switched my major to civil engineering. I like the math and the mechanics, but I don't like having to learn about electricity (although it may just be my physics II professor and the lab TA). Do civil engineers ever actually work with electricity? meaning will I ever use this...
As it is said , if we hold the higher potential of a battery via a wire without touching the ground, some of the static electricity gets stored into us. Does that mean that the voltage of the higher potential reduces due to loss of charges.
Homework Statement
In the circuit shown in the figure above, the ammeter reads 3.4 A and the voltmeter reads 6 V. Find the emf ɛ and the resistance R.
Homework Equations
Ohm's law; V= I*R
EMF equations: ε=I*r+I*R
ε=I*r+V
The Attempt at a Solution
[/B]
I got the...
I have a knife(and perhaps a utensil too? and also a plastic bottle?), I am in a biome of some lattitude and longitude. I have a phone/bulb/radio/whatever needs very little energy, but they're discharged. Theres no plug anywhere, I am in the middle of nowhere. What contraption should i make to...
According Ohm's laws V=IR , which means voltage is directly proportional to electricity, but according to the formula of P=VI= V=P/I, voltage is inversely proportional to electricity, so what's wrong here?
So,the thing is i want to convert distortions generated in two RF signals in Electric energy.
Actually i want to store it and then use it. example- Charging my smartphone.
So what will be the basic requirements for me to do so!
Homework Statement
a small spherical insulator of mass 6.00×10−2 kg and charge +0.400 μC is hung by a thin wire of negligible mass. A charge of −0.220 μC is held 0.290 m away from the sphere and directly to the right of it, so the wire makes an angle theta with the vertical. What is the angle θ...
If:
1) you know the vertex and individual charge of each node and
2) voltage is the difference in electric potential energy between two nodes
How do you calculate the voltage in a vacuum?
if an voltage is applied in an electric circuit connected to a resistor voltage drops across the resistor right? how much time it takes in that process?
does it occur instantly?
I have read Tesla's patent and he claims that by rarefying the air enclosed in a vessel its insulating properties are impaired to such an extent that it becomes what may be considered as a true conductor, although one of admittedly very high resistance.And any amount of electrical power can be...
What effect (if any) would changing the surface area of electrodes in a lithium ion battery have?
Would it allow for faster battery charging? Faster discharge rate?
Thanks in advance
I'm looking into building a 7 1/4 gauge Diesel Electric Locomotive
I will be using 4x 1hp (or 1 1/3hp) 24vDC permanent magnet motors for the traction motors. What I am looking for is someway of generating 24vDC with a 100-150A max output. (Im using a 3cyl 16hp Diesel engine to drive a...
Homework Statement
Two 3.0 cm diameter disks face each other, 1.9mm apart. They are charged to $$\pm 16nC$$.
(a). What is the field strength between the disks?
(b). A proton is shot from the negative disk toward the positive disk, what launch speed must the proton have to barely reach the...
Homework Statement
Okay so we are given this circuit. I do not want to be told step by step what the answer (or worked solution is) but I am wanting some guidance about how I can start/continue on from what is given to us.
We obviously need a understanding of Kirchoff's current law.
Our task...
Suppose I first charge a capacitor so that one plate is positively charged and another negatively. Now I remove the charging source and ground only one of the terminals say negative terminal, will there be a net positive charge in the capacitor that can be detected by a pith ball?
Can a...
Homework Statement
I'm looking at an E&M textbook - "Time-Harmonic Electromagnetic Fields". They state:
"A more general ##x ## polarized field is one consisting of waves traveling in opposite directions with unequal amplitudes - i.e :
(1) $$ E_{x} = Ae^{-jkz} +Ce^{jkz}$$
Let ## A ## and...
1.Is electric current a microscopic or macroscopic quantity?I think it is macroscopic as we can feel it,but when I asked my friend he said it is microscopic as it deals with electrons.I'm a bit confused...
2.What is the speed of electricity?Is it equal to the drift velocity of electrons or the...
Homework Statement
Hi all,
I have this quiz on MasteringPhysics, but I can't seem to get the right answer.[/B]
Consider two positively charged particles, one of charge q0 (particle 0) fixed at the origin, and another of charge q1 (particle 1) fixed on the y-axis at (0,d1,0). What is the net...
This is something I have been trying to figure out lately, but I can't seem to wrap my head around it.
So, according to a definition in my Physics textbook, while the electrical potential difference established between two terminals encourages the movement of charge, it is resistance that...
Edit: sorry i realized i posted this in the wrong section. Can some move it to hw? Thank you.
Hey i was studying intro E&M recently and i started learning about RC circuits. Up until this point everything, concept wise, has made sense for me. Then I learned how RC circuits work, and the math...
conduction of electricity in electrolytes is due to presence of positive ions and negative ions or presence of positive ions, negative ions and electrons?
I'm setting up an amplifier which is intended for use in a car, and I'm not using it in one. I'm trying to power it through a typical DC 250 volt wall outlet. What kind of transformer should I use? (I'm also trying to power a car stereo with it as well)
Homework Statement
1. Explain why a balloon sticks to a wall after being rubbed on your shirt (remember the wall is not metal and does not have "free" electrons")
2. Include a balanced force diagram that includes the electrical force and gravitational force (assume electrical force is twice...
Hello
I made a little wind turbine so when it is directed at wind it turns and generates electricity as I can see the outcoming voltage on voltmeter. My question is how can I store its energy?
Can I use a rechargable battery and let it run out, then stick copper wires at each sides of it coming...
In Indian standard electric supply at homes is of 220V and 50Hz, What is the physical meaning of Voltage 220V? Does Voltage means Potential difference? I know that potential difference(pd) between two points is the work-done per unit charge to move it between the two points. Is 220V the pd...
may I know if there will be potential difference if there is no resistor in a circuit? If the positive terminal of a battery has a high potential in terms of conventional current, then in electron flow, does it mean that the negative terminal has a high potential?
What is the best way to produce electricity?
Nuclear : people are afraid of leaks and waste storage problems.
Coal: People are afraid of smoke pollution, and it may run out soon.
Oil same as above.
Wind inefficient and to costly.
Wave renewable but again too costly
Solar: it takes up to much...
I was reading through a paper about the first case of experimentally proving that electron transfer can occur over the length of a bacterial nanowire. The paper mentioned that, previously, electron transfer was only measured across the thickness of the wire.
"Thus far, there has been no...
Homework Statement :[/B]
When a steady current flows through a conductor, the electrons in it move with a certain average 'drift speed'. The drift speed of electrons for a typical copper wire is about 1 mm s-1 . How is it then that an electric bulb lights up as soon as we turn the switch on...
We've got a scalable sun tracker that requires no electricity. See << Link removed by Moderator >> Though invented for use as a less expensive alternative to the traditional electric motor solar trackers, we have come to realize that it can actually lift a lot of weight. We haven't tested the...
I have some trouble grasping voltage, and why it is defined by V = R * I.
1. If voltage can be seen as some form of electrical potential energy, why does it not increase as the circuit is made longer (in terms of meters). Would a current be as likely to travel in a 0.1 meter circuit as in a...