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'm looking for a way to use these batteries that is safe and also useful. I've looked into buy inverters to turn them into portable battery packs but am out of my depth and don't want to create a device with serious potential fire hazards without thoroughly understanding the ins and outs and...
I have tried to solve the problem by setting as a condition that the electric field inside the conductor has to be 0, but in this way I have two unknowns (σ1 and σ2):
Electric Flux = E*A = 5*6(0.05)^2.
when i look up at other sources they use Electric flux = q/ (8.854*10^-12 [this is e]) equation
but I am confused on why the E*A equation don't work. The answer is 0.02Nm^2/C
Hi folks,
I'm searching for information/procedure and also calculations/equations on how to correctly wind a stator on a (general or DC 3-phase) brushless motor? I.e. how to wind a copper wire X number of times around the stators, and thus get the desired performance/force that is required...
According to the circuit in the figure; Can you calculate the values of the currents I1, I2, and I3.
Can you send me a detailed solution to understand?
Given the total angles in the x direction, I set up this:
(mg/cos(x))*sin(x)-Fe=0
then isolated for x:
mgtan(x)=(kq^2)/(2*sin^2x)
sin^2(x)*tan(x)=(kq^2)/(2mg)
From here I am stuck. How do I go forward when x is contained in two different trig functions on the left?
Summary:: I try to find the resultant force on "q". I think I have to find the value of Q, but I'm not sure.
I Know F1 = k|q * 2Q| / 3² and F2 = k|q * Q| / 2²
Hi,
this is my first post on this forum I hope I posted in the right section.
I try to find the resultant force on "q". I think I...
The load system formed by the point load and the load distribution generates two regions in space corresponding to r<1m and r>1m, i.e. inside and outside the sphere. Given the symmetry of the distribution, by means of the Gaussian theorem we can find the modulus of the field at a distance r from...
Mentor Note -- Thread moved from the technical forums, so no Homework Template is shown.
So, we've conducted an experiment on resistors in a circuit. The theoretical calculation was based of on E-24 series color band table and the measured resistance of the resistor was measured by a meter...
My question might sound stupid to you but please clear my confusions.
I'm taking an circular arc like element on the plate. That arc has a radius of 'r' (AB) and the radius is inclined at an angle 'θ' with OA (∠OAB).
The area between arc of radius r and r+dr is dA.
dA = 2θr.dr
The charge on...
I read about electric armor (also known as dynamic armor or electric reactive armor) that can protect armored vehicles from shaped charges of anti-tank weapons and I want to know if its feasible today.
according to wikipedia:
[Moderator: please don't do this without a link. The link is The link...
Homework Statement
We have an incident electric field, and there are two cases:
1) the field is polasised perpendicularly to the incidence plane (TE)
2) polarised in the plane (TM)
Here I must be able to correctly apply the limit conditions, to find the Fresnel formulas that give the...
if we had an entire car made of Starlite (a material that was created resistant to 18032 °F). Would the efficiency of the combustion engine be close to that of the electric and that of the electric would be almost 100% efficient?
https://en.wikipedia.org/wiki/Starlite
I'm looking for advice on how much power is required to compress air in a gas turbine engine - parameterised by degree of compression and mass flow.
Normal gas turbine engines have exhaust turbine(s) on the same shaft as the air compressors. They bleed some of the exhaust energy to drive the...
Ok so she says that electric dipoles are of opposite charge but equal magnitude at 3:40. But then at 5:33 she shows 2Q with -Q, at that point the magnitude of the 2Q particle wouldn't be equal to the -Q so they wouldn't be electrical dipoles right?
Good day all,
This is my first post here, hope you all are able to help me out here.
I am thinking about converting an old Suzuki GS500E from an internal combustion engine to an electric motor.
At the moment I am having some difficulties with the physics side of things, I would like to...
Homework Statement
Homework Equations
Kirchoff's Rule
The sum of all V = 0
The Attempt at a Solution
[/B]
I think I'm having a problem determining the current at r_2 and R_3. I had originally thought the currents at both resistors would be I_3, writing E_2 — r_2 I_3 — R_3 I_3 — I_1 R_1 = 0...
https://phys.org/news/2018-03-world-first-air-breathing-electric-thruster.html
If it dipped into the atmosphere temporarily on an elliptical orbit, could the air gathered be stored for a long flight? Then maybe get more fuel from another planet's atmosphere or moon for the return trip?
Hello,
what is the consensus on using super capacitors to power a 500w electric bike motor.
cheap and innovative alternative to li-po batteries or explosion between thighs waiting to happen?
the plan is to create something like this:
i will use a 24V motor...
Hello,
I'm currently constructing an electric bicycle using a 500w 24v motor, 2X24v 7ah batteries (maybe 4 later on). I bought a 24v 30a dimmer switch to use as a "throttle". During the intitial test (on a table, not on the bike!) It worked absolutely fine for 2 minutes, but then began to smoke...
Homework Statement
The figure below shows a spherical shell with uniform volume charge density ρ = 1.87 nC/m3, inner radius a = 15.0 cm, and outer radius b = 2.60a.
[Reference Picture]
What is the magnitude of the electric field at the following radial distances?
Homework Equations...
Let's consider that I have an emitter that can emit both negative and positive electric charges. Here let's consider only scenarios with two particles (one negative and one positive) that start initially at the tip of some electrode, where one or both the charges will separate from at the same...
Hi.
I know how to use Gauss' Law to find the electric field in- and outside a homogeneously charged sphere. But say I wanted to compute this directly via integration, how would I evaluate the integral...
Homework Statement
[/B]
A screenshot with everything given
Homework Equations
No idea
The Attempt at a Solution
No idea
I'm not sure how to solve this or where to look for a solution. I was given this yesterday and have a test tomorrow. The professor has not gone over this at anytime...
TheRealBillNye
Thread
circuit
circuit analysis
electric
help i'm lost
voltage
Homework Statement
A region of space has a non-uniform electric field that points in the +x-direction and has magnitude as shown in the figure (Figure 1) As a reference point, take the potential at the origin to be -140 V .
Calculate the electric potential at x=3.0m.
Express your answer to two...
Homework Statement
A uniform electric field exists in the region between two oppositely charged parallel plates 1.59 cmapart. A proton is released from rest at the surface of the positively charged plate and strikes the surface of the opposite plate in a time interval 1.50×10−6 s .
Find the...
Hi, I own a 1993 ex500 with that is having engine problems, I would like to swap the motor for one that is has more or equal power. The best specs I can come up with are these the motor puts on the rear wheel, HP 50, Torque 31 ft-lbs, top speed 130mph, I am looking into getting a DC-liquid...
Hi.
I fear I might not have understood some fundamental concepts about electric power transmission. So we have "neutral" which is brought to Earth potential. Does this mean the electrical circuit from the power plant over highly conductive aluminium cables to my home closes back to the power...
Homework Statement
Design a series RLC filter for 10kHz using an 0.01mF capacitor.
Homework Equations / 3. The Attempt at a Solution
how would the circuit actually look if drawn out here?
[/B]
Homework Statement
1. The field for an infinite charged sheet is found to be σ/2ε0. If we place 2 infinite sheets of opposite charge above one another, we say that the field in between the sheets is σ/ε0 due to the superposition of individual fields.
Why can't we say the same for a situation...
For static electric fields? does it apply also for a generic electric field? Let's say, moving charges inside a closed surface?
If there are charges accelerating in a closed surface a part of the electric field is due to the charges, and a a part is due to the fact that the charges acceleration...
Homework Statement
Two cylindrical resistors are made from the same material and have the same length. When connected across the same battery, one(A) dissipates twice as much power as the other(B).
Find ratio of dA/dB.
Homework Equations
P = VI = V2/R = I2R
Area of cylinder = 2πrh + 2πr2
The...
Homework Statement
A cubical region 1.0 m on a side is located between x=0 and x=1 m. The region contains an electric field whose magnitude varies with x but is independent of y and z: E=E0(x/x0), where E0 = 32 kV/m and x0 = 6.0 m . The answer needs to be in μ J.
Find the total energy in this...
Homework Statement
Homework Equations
The Attempt at a Solution
I have the complete solutions for this problem, I just don't understand them:
This is the first part. I don't understand what r' is, or how we found it. Otherwise I understand the concept of the problem just not the details...
Chapter 24, Question 61
Given two configurations, ##C_1##, ##C_2## of ##N## point charges each, determine the smallest value of ##N## s.t. ##V_1>V_2##.
##C_1##:
##N## point charges are uniformly distributed on a ring s.t. the distance between adjacent electrons is constant
##C_2##:
##N-1##...
Homework Statement
In the following picture, the absolute value of the difference in electric potential, between points A and B is:
A)5V
B)4V
C)3V
D)1V
E)0V
Homework Equations
E =qV
V = iR
The Attempt at a Solution
I have no idea where to start on this one, just started my electric...
Homework Statement
I have three questions spanning three different situations, but each deal with the single concept of electric flux.
Problem 1: Write an expression for the net electric flux through the entire surface in terms of the area vectors and the electric field E.
Problem 2...
Homework Statement
Not so much of homework questions but more to do with clarifying concepts:
1. How do i assess whether or not field lines emitted by charged objects (i.e uniformly charged cube) are both perpendicular to their surfaces uniform? This is in relation to taking the E of ∮φ = EdA...
Homework Statement
[/B]
Find the electric force between the two spheres.
Sphere r=b-a has a volumetric density of p=K, where K is a constant
Sphere r=a has a volumetric density of p=θ*r
Homework Equations
As you can see the sphere of radius 'a' doesn't have a uniform electric field because...
Please explain how or why (I have zero knowledge in physics)..
1. is Voltage the energy required by the elctrostatic forces between 2 points to move a certain quantity of charge between them?
2. Why is it called potential difference? Does this have to do with the difference in potential energy...
Homework Statement
What is the magnitude E of the electric field at point P? Throughout this part, express your answers in terms of the constant k, defined by k = 1/(4πE0)
To solve this question, I am trying to walk through the hint process.
Question 1: Find the magnitude dE of the electric...
What formulas do Diesel Electric Locomotive manufactures use when designing new Locomotives? Are there any good books on the subject? Locomotive meaning train engine. I want to understand freight engine designs not passenger.
Thank you,
Kevin
Hello all. I am working on a research project involving the Stark effect and its application in molecular guides and came across a bit of math in a paper that I don't understand. In this paper http://arxiv.org/abs/physics/0310046 there is an equation in the introduction concerning the electric...
Homework Statement
Is there a difference between electric, electrical and electrostatic force?
Homework Equations
The Attempt at a Solution
I used them interchageably. Is it incorrect?
When calculating the electric field from a point above a line of charge using coulomb's law, the integral that comes up is of the form \int { \frac { dx }{ { x }^{ 2 }+{ a }^{ 2 } } } . But if the point we were asked for is right in the middle, the horizontal (cosine) components cancel out...
It's just that I've never properly sorted this confusion of mind, so i would like to sort it out
so it 2 different capacitors are in series with a resistor: (let's say 0.15F, 0.45F, 150M ohm)
1. both current and voltage drops exponentially
2. capacitance on capacitors remain same over time?
2...
Hello experts...
I have an experiment pool boiling. The test section filled with DI water, and use thin flat copper as the heater that connected to the power supply.
I want to ask how to measure or calculate the heater temperature if I only have the resistance, voltage and current data reading...