In physics and electrical engineering, a conductor is an object or type of material that allows the flow of charge (electrical current) in one or more directions. Materials made of metal are common electrical conductors. Electrical current is generated by the flow of negatively charged electrons, positively charged holes, and positive or negative ions in some cases.
In order for current to flow within a closed electrical circuit, it is not necessary for one charged particle to travel from the component producing the current (the current source) to those consuming it (the loads). Instead, the charged particle simply needs to nudge its neighbor a finite amount, who will nudge its neighbor, and on and on until a particle is nudged into the consumer, thus powering it. Essentially what is occurring is a long chain of momentum transfer between mobile charge carriers; the Drude model of conduction describes this process more rigorously. This momentum transfer model makes metal an ideal choice for a conductor; metals, characteristically, possess a delocalized sea of electrons which gives the electrons enough mobility to collide and thus affect a momentum transfer.
As discussed above, electrons are the primary mover in metals; however, other devices such as the cationic electrolyte(s) of a battery, or the mobile protons of the proton conductor of a fuel cell rely on positive charge carriers. Insulators are non-conducting materials with few mobile charges that support only insignificant electric currents.
An irregular neutral conductor has a hollow cavity inside of it and is insulated from its surroundings. An excess charge of 16.0 nC is sprayed onto this conductor.
A) Find the charge on the inner surface of the conductor.
B) Find the charge on the outer surface of the conductor.
C) Without...
Homework Statement
Why is the electric field, in static equilibrium, equal to zero.
The Attempt at a Solution
The only way I can see why is to picture that there was an electric field inside a conductor. The field would cause the electrons to move freely inside the conductor. This...
The image below is from giancoli. There is clearly an electric field inside the conductor, going from the + charge on the outside surface of the wheel to the - charge on the inside surface of the wheel. There is an electric field inside this conductor because if I drop a + test charge in the...
Homework Statement
The potential outside of a spherical conductor is given by V = keQ/r. Using Er = -dV/dr, derive the electric field outside this charge distribution.
The Attempt at a Solution
I attempted to take the negative derivative of V being -1/(r2) and then multiplying it...
Homework Statement
Two charged spherical conductors are connected by a long conducting wire, and a charge of 22.0 µC is placed on the combination. If the first sphere has a radius of 4.49 cm and the second has a radius of 5.68 cm, what is the electric field near the surface of each sphere...
Homework Statement
At the surface of a conductor the potential is constant .. I can't get my head around this ..
Homework Equations
E=-grad VThe Attempt at a Solution
The only reason I can think about this is Electric field is perpendicular at the surface , hence no work is done when moving...
Hi! I'm stuck on a problem concerning the magnetic field produced by a long straight conductor:
A triangular piece of conductor (N=1) rests in the vicinity of a long straight conductor with a current I=50A. What is the magnetic flux through the triangle if a=1cm? (See attached file).
My...
Homework Statement
Please check attachment or picture below
http://i.imgur.com/ALG5d.png
Homework Equations
The Attempt at a Solution
Probably I should consider it as a capacitor? For a conductor, is that means no charge inside, charges are all on surface?
Thanks!
Homework Statement
A cylindrical conductor of radius R = 2.49 cm carries a current of I = 2.17 A along its length; this current is uniformly distributed throughout the cross-section of the conductor. Calculate the magnetic field midway along the radius of the wire (that is, at r = R/2)...
If I put a charge inside a hollow conducting body is it true that the field lines from the charge don't penetrate through the conductor but instead terminate at induced charges on its inside wall?
Will a current through the ptype + metal material be very low because of the ptype material?
Does a junction like a pn junction form between the ptype semiconductor and the metal?
Thanks for your time.
hi all expert...
During my study on physics book is borned in my mind this question:
I have two conductors with the same material, same length and same diameter...In one conductor is carrying 1000 Ampere in A.C. and in other conductor is carrying 1000 Ampere in D.C.
If i check the magnetizing...
Homework Statement
A light bulb with resistance R is attached on a metal rod which is rotating around the point O on the figure. The metal rod is in contact with an electrical conductor which is a part of a circle with radius d. The metal rod and the circular electrical conductor is a closed...
Friends:
Lets say you have a conductor that is made of two components - an inner core of steel and an outer layer of aluminum (ACSR). Is there mutual inductance between the steel and the aluminum? Every example of mutual inductance I have seen requires that an insulated wire be wrapped around...
1. Electric potential inside a conductor / outside a coaxial cable
Electric Potential inside a conductor(spherical) is a constant, although electric field is zero. How does that make sense given:
Given V=- \int E \cdot dl?
The integral should be 0. Even if you consider constants of integration...
Homework Statement
Two charges, q and q', are located respectively, inside and outside a hollow conductor. Charge q' experiences a force due to q, but not vice versa. Prove this statement and explain the apparently violation of Newton's third law. There is no net charge on the conductor...
Friends:
I have been wondering how a conductor's tension is affected by birds landing on it and then flying away. By itself, the conductor has some tension obviously due to its weight. When a bird lands on the conductor, the tension increases. But what about when the bird flies away? By...
Why is it that whenever the method of images is used to solve for the induced charge on a grounded conductor in the presence of a point charge, the total charge is just the same as the image charge?
Homework Statement
Hi, this is the first time I post a thread in this forum.
I am not sure if I could post this question here since it is not a homework problem.
I have trouble understanding two boundary condition between nonconductor and conductor from Maxwell's equations in dynamic case...
Homework Statement
Consider a segment of a toroidal (doughnut-shaped) resistor with a horizontal cross-section (see attachment for the figure). Show that the resistance between the flat ends having a circular cross-section is given by
R = \frac{\phi_o}{σπ(√b-√a)^2}
Homework Equations...
Why should the force on a point charge always be toward a neutral conductor? I know this is a simple concept, but I'm having trouble grasping it.
Any ideas?
Thanks!
An initially neutral conductor contains a hollow cavity in which there is a + 65.0 nC point charge. A charged rod transfers - 75.0 nC to the conductor.
Afterwards, what are the charges along the inner surface and the exterior surface?
I understand that the charges from the rod are equally...
Homework Statement
A spherical conductor of radius a is surrounded by a spherical conducting shell of radius b, and the gap is filled with an insulating material of resistivity ρ. A thin wire connects the inner surface of the shell to the surface of the conductive sphere, and a potential of...
Homework Statement
Help me understand why electric potential can ever be a nonzero value at a point within a charged conductor? I need conceptual reasons to help me make sense of the integration "flaw". (See below.)
Homework Equations
The electric field inside a charged spherical...
Homework Statement
A rectangular hollow conductor,open at one end of z, has a voltage impressed at z=0. On the z=0 plane, the voltage as a function of x and y is simple cosines such that V=0 at x=y=+/-L/2. All other surfaces are grounded.
V(x,y)\approx f(cos(Ax),cos(By))
Calculate...
Homework Statement In the following diagram, the brown metallic conductor rod is given a slight push to the left.
The black lines are all conducting wires, with the entire setup placed in a perpendicular B-field. Ignore friction.
What will happen?
1) The rod slowly come to a stop?
2) The rod...
I can understand that if there is no charge inside an object then the electric FLUX is zero. Meaning the net integral of field vectors with respect to the area will be zero. But that doesn't mean there are no field lines inside the object at all! does it? I thought it just meant that the number...
I am trying to understand the magnet and conductor problem that Einstein mentions at the beginning of one of his 1905 papers.
In the frame of reference of the conductor, the magnet moves. Why does this mean that Faraday's law is applicable and not Lorentz force law?
In the frame of...
As we know, plastic is non-conductor, iron metal is conductor, does anyone have any suggestions on what kind of property in term of molecule structure allows electricity to get through?
Thanks in advance for any suggestions
Homework Statement
for my assignment given i was told to derive the equation of the skin depth of a good conductor and i derived it as
d=sqrt(2/\mu\omega\sigma)
then i was told to calculate d where i was given w=10^15 and sigma=10^7 and this gave me a d of d=1.26E-8 which i guess is...
I'm trying to find the electric potential inside a thin (not charged) spheric conductor of radius R, containing a point charge of charge +q exactly in the center.
To do this, I'm trying to solve the differential equation \Delta V = 0 (harmonic). Together with the boundary condition V(R) = c...
Hello,
in this diagram, the shaded regions are spherical conductors.
What's the potential at A=B?
Ignoring the outer sphere, it should be kQ/R.
When you add the outer sphere, potential at C=D=0 and electric field between B and C is kQ/x^2
so i integrated (kQ/x^2) dx with interval [2R, R]...
Homework Statement
A point charge Q with mass M approaches a semi-infinite surface of a perfect metal and becomes trapped near the surface in a (quantum) bound state. Find the binding energy of this particle to the surface. Treat the metal classically—i.e. ignore its internal quantum levels...
My question is related to the gaussian surfaces, a planar conductor and an infinite sheet.
The E field outside of this sheet is sigma/2*epsilon naught
The E field outside of this conductor is sigma/epsilon naught, twice as strong as the infinite sheet.
I understand the...
Hi
I want to find the magnetic field result from DC current flow through the rectangular transmission line numerically by using the finite difference.
the solved equation is curl curl A =µ J , with div A=0, and J is a uniform current on the crosssection.
I implement the MATLAB code , but...
Good afternoon,
I was self-studying Electricity (Gauss' Law) and I have a doubt regarding the electric field near the surface of a conductor.
I know that, near the surface of an infinite plate made of a non-conductive material, the electric field can be given by:
E=\frac{\sigma}{2\epsilon_0}...
Hii , i am new in this forum . I am in class 10th and my name is Sankalp . I have a question :
Can you tell me why copper is better conductor of heat than iron ??
This is just a hypothetical questions, but...
Would it be possible to have a capacitor so large that its able to store all the free electrons in the wire in the circuit its attached to?
Then, this would mean all the free electrons have been removed from the wire, thus making the wire non...
Hi there,
My boyfriend and I have been bashing our head against this past exam question for some time now, any physical insight would be appreciated.
Homework Statement
A long straight conductor has a circular cross-section of radius R and carries a current I. Through the conductor...
Homework Statement
Find the induced emf in a rotating disc of radius (a) in a magnetic field (B), rotating with uniform angular velocity (w). If the disc is replaced by a rotating conductor of length (a) fixed at one end find the induced emf in the conductor.
2. The attempt at a solution...
Homework Statement
How does the electric current flow through this circuit?
2. The attempt at a solution
It would make sense for me to take the path where there's no resistance and skip the path with the resistance R1, but I'm not 100% sure about that.
So how does it flow? pic1 or pic2...
What happens if I place a solid conductor in a static B field. I mean B fields can't do work so it won't induce a current unless its a superconductor. Will it shift the electron orbitals because of the Lorentz force? Any input will be much appreciated.
Hey all!
I've return back to my year 12 assignment, the railgun. I got a working model back then, but unfortunately didn't write up a good report. I have the videos on youtube if anyone is interested.
The reason for the conductive liquids is because I want to tackle the arcing issue.
I...
Hi all,
I need some help understanding why exactly there is no electric field inside any conductor (charged or uncharged). I am in year 12, and I would like to understand the reasoning behind it in terms of the MOTION OF CHARGES in the conductor.
What I know so far:
- Charges (electrons)...
Homework Statement
A hollow sherical conducting shell is suspended in air by an insulated string. The total charge on the conductor is -6 microCoulombs. If an additional point charge of +2 microCoulombs is placed in the hollow region inside the shell what is the total charge induced on the...
I have written this problem myself to present to my professor. He teaches HVAC and Electrical for the department of Construction Management. Some of the problems and solutions we do in class are inconsistent with the material I was taught in physics. He really appreciates my criticism and I...
Homework Statement
The problem asks us to find the magnetic field inside a coaxial conductor that consists of an aluminum wire of radius r1 surrounded by a cylindrical aluminum shell of inner radius r2 and outer radius r3. I know how to do this, but it also says that there is oil flowing...