Conductor Definition and 790 Threads

I don't quite grasp this statement : Open attachment to view the image of what's going on The field from a positive charge Q pulls electrons to the surface of the metal nearest Q, leaving a net positive charge on the surface farthest from Q. The fields of these induced charges resting on...

Homework Statement A spherical conducting shell of inner radius a and outer radius b contains a centrally-located point charge +Q. Is an electric field present at radii (i) less than a, (ii) between a and b, and (iii) greater than b? Homework Equations The Attempt at a Solution...

Hi experts, I still do not understand how positive charge is distributed inside a conductor. In case of extra electrons is it quite evident, as they are free to move and repel each other, so they go as far away as they can. But what exactly happens if electrons are removed from a conductor...

ok so here is the question number 45 and its second part and this is what i did I have a c magnet drawn with the north pole and the bottom opening right. And the magnetic field lines running between the two polls (virtically) And I have a conductor running between the poles...

How do I calculate the charge distribution on the surface of any asymmetric closed conducting surface? Is it possible for me to calculate the surface charge density 'σ' as a function of '\bar{r}' the position vector in a spherical co-ordinate system in space, provided I know that the conductor...

Hi, I consider a connected conductor. Is it right, that: 1)the potential at any point of the conductor is the same, but 2)the absolute value of the potential isn't zero in general? I think these statements are true, but I'm not sure about it, especially with the second statement...

If a neutral conductor gets an induced charge and is then grounded, will electrons from the ground flow into the conductors induced positively charged side, resulting in a net negative charge for the whole conductor?

I've noticed that almost every good conductor of electricity, is also a good conductor of heat, except for certain exceptions like Graphite. Why is this so? I can't seem to associate electron flow with heat conduction.

Hey guys, I'm hoping someone can help me out, as i have an exam tomorrow and have no began panicing as I've found a question i can't seem to get to the end of... Here is the question itself; A large crucible contains a metal of thermal conductivity, κ = 12.5 Watts. m-1.K-1, electrical...

1.Why electric field is zero inside a conductor? Can anyone explain it with Gauss's law and without Gauss's law? 2.Is it possible to create electric field inside a conductor? If so,how and in which condition it is created?

Homework Statement A proton (q = 1.6 x 10-19C; m = 1.7 x 10-27 kg) is in a uniform 0.25 T magnetic field. The proton moves in a clockwise circle with a tangential speed of 2.8 x 105 m/s. What is the radius of the circle? Homework Equations Not sure what equation to use. The...

Hey All, I'm new to the forum. I hope I put this in the right area of expertise. If not, I would appreciate it if you could direct me to the right place. I am just a curious person with a pretty good physics background but I came up with a question I couldn't answer. Hypothetically, if you had...

Let's say we have a charge a distance d above the xy plane, which is a grounded conductor. Find the potential at every point. Now this is not a hard problem if you know the method of images. I do however have some questions: 1) The idea is, as reader probably knows, to solve poissons equation...

i am really really confused . I know what Drift velocity is but the problem is I have three Sources which tell absolutely different expression for drift velocity and I cat relate . please tell which is right . This website and MIT Profs. Walter Lewin In his Lectures says Vd = eE/m x (Tau)...

A conductor, like a metal string, is moving in an electric field. The metal string is under mechanical tension and is electrically connected to a resistor. The other end of the resistor is connected to the remaining end of the string. The electrical field is the static field of an electret...

Homework Statement Fig. 1 shows the cross-section of an infinitely long conducting pipe. The inner radius of the pipe is r = R1, and the outer radius is r = R2. Suppose the inner surface has a constant voltage V = Vc > 0, and the outer surface has a constant voltage V = 0. The voltage...

This doubt cropped up in my mind while going through my old electrostatics notes... We consider a spherical shell with some thickness (so that two different charge distributions may be possible on the inner and outer surfaces of the shell) made of some conducting material, and electrically...

Homework Statement A conductor with inner radius R and outer radius 2R. A charge q is kept at a distance d<R but it is not at the centre. What will be the electric field outside the conductor? Will the charge distribution be uniform? Homework Equations The Attempt at a Solution i...

Homework Statement Prove that there is no charge inside a SOLID conductor, and thus, charges are only on the surface. Homework Equations Gauss's Law (Maybe) The Attempt at a Solution I have been doing some research on it on some websites. It mentioned that, "you make a Gaussian surface...

i've been thinking about creating some sort of taser like weapon. As we know, taser range is limited by the length of the wire and the weight of the electrode. So it's only usefull over short distance. What intend to create is some sort of stunner beam. Here's how it'll work. the first part...

Suppose there is a cavity inside a conductor. Outside the conductor there is a point charge (A). E inside the cavity is zero because the field from the conductor and point charge cancel. That I believe. Suppose I add a point charge (B) inside the cavity. Obviously, there is a radial...

Let's say we have 2 different conductors - one a round wire, another a round wire but with hollow core. The wire with the hollow core has higher resistance. But for the sake of argument, let's assume that it has the same resistance and the round wire. Will the skin effect be less for the...

Homework Statement Two infinite plane lattices (conductor) of uniform thickness t1 and t2 respectively, are placed parallely to each other with their adjacent faces separated by a distance L. The first lattice has a total charge by unit of area (the sum of surface densities of each sides of...

Hello, I'm having some issues with Love's equivalence principle. I'm studying Balanis' "Antenna theory" (1997), here's a (legal) fragment of the section in question: http://www.uniroma2.it/didattica/ap1/deposito/02_2-Balanis-Equivalence_Theorems.pdf I'm trying to understand the following...

Homework Statement The figure shows an end view of two long, parallel wires perpendicular to the xy-plane, each carrying a current I but in opposite directions. Derive the expression for the magnitude of B at any point on the x-axis in terms of the x-coordinate. Homework Equations...

Homework Statement Homework Equations All explained in my solution attempt The Attempt at a Solution Let me know what's going wrong here. I don't feel like I should be getting something as small as t = .05 seconds for an answer.

I'm a little bit confused about this...i know that when a current-carrying conductor is placed in a magnetic field, it experiences a force called Lorentz force, this is the formula: F = Bil but the thing i can't understand is whether this FORCE is perpendicular to the magnetic field or the...

Hi was wondering if anyone knows how to calculate the tension in a overhead conductor say 'Dog' conductor over a 100m Span with a wind of 900Pa given its properties are as below 'Dog' Conductor properties Diameter = 14.15mm Weight = 0.3965kg/m Area = 118.8mm^2 CBL = 32.7kN Expansion...

how do i measure temperature of a current carrying conductor? i need to know the increase in temperature as i heat it up by passing a current through it. i read somewhere that i could use heat transfer convection equations to find it, but then i would need the precise value of the heat transfer...

Homework Statement Calculate the drift velocity of the elctrons in a conductor that has a cross-sectional area of 8x10^-6m^2 and carries a current of 8A. Take the concentration of free electrons to be 5x10^28 electrons/m^3 with 1.6x10^-19C charge on each electron. Homework Equations...

Hi, I'm new to the forums, and I have a question. Here's the scenario: Let's say I have a circuit in a vacuum chamber with a current i, that flows through it and a constant voltage source and resistance in the circuit. One section of the circuit is a piece of gold (or any other conductor)...

Homework Statement A 500 mm conductor inside an electric motor has a force of 1.5 Newtons exerted on it. If it is at right angles to a magnetic field of flux density 0.6 T, calculate the current flowing in the conductor. Homework Equations F=B.I.L The Attempt at a Solution B = 0.6T F =...

A metal wire slides on a horseshoe-shaped metal loop of width 0.25 m. The loop has negligible resistance, but there is a 1Ω resistor in the circuit as well as a 6 volt battery. There is a uniform magnetic field directed into the plane of the page of magnitude 0.5 T. The slide wire is pushed...

Homework Statement The electric field is zero within the conductor because the charges are all at rest in an electrostatic situation. But the electric field inside a cavity within the conductor is not necessarily zero because it isn't part of the conductor, as my book says. Then i encountered...

If specs on a 300Hp electric motor; 480 Volts 3 Phase 60Hz The full load Amps of the motor is 361A, which I found in the NEC table. My distance is 700ft to a control center and I can't seem to figure out what copper conductor size to use. In order to find the Voltage drop I have to know...

Hi everyone, The field inside a conductor and also inside any voids in a said to be zero. I'm convinced with the available proofs for the field inside a conductor. However, I am not aware of any solid proof for the field inside a void in a conductor. Would you please share your knowledge on...

Problem: Calculating the eddy current distribution inside an infinitely long cylindrical conductor inside a straight and infinitely long solenoid energized by an alternating sinusoidal current. The problem has a perfect summery and we know that magnetic field and the eddy current depend on...

My textbook (Halliday & Walker) explains that a charged conductor (a solid, of an arbitrary shape) in electrostatic equilibrium will have the electric field inside be 0 and all electrons will be on its surface. It proves this by saying that if the electric field inside was not 0, the free...

Homework Statement Hey guys, new to the forums so hopefully you can help. I have been given the frequency (and hence the wavelength) of a microwave of 10GHz, and the conductivity of Al which is 3.53x10^7 Siemens/m. From this I have worked out the skin depth. But it asks also what the...

electric field "inside" conductor Well consider a conductor with a void inside it. An external constant electric field is applied across it. I would like to distinguish between two things : when i say "inside" the conductor i mean the void, the empty space which contains nothing but air and...

As we say that current is the flow of charges, but if we dye a conductor with red color and then connect the terminal with the dc source. Now as the current starts flowing through this conductor and we say current is the flow of electrons or charges then why the red color around the conductor...

Hi, I was reading some text and came across this problem, the problem is also mentioned in this link from Wiki: http://en.wikipedia.org/wiki/Inductance#Self-inductance They said that it is because the 1/R now becomes infinite, this is what I'm confused about. From my understand, there would be...

Imagine an uncharged spherical conductor centered at the origin has a hole of some strange shape carved out inside it, and a charge q is placed somewhere within this hole. What is the field outside the sphere? Is it even possible to determine the electric field simply from the given...

Homework Statement In case of having a conductor (spherically shaped and uncharged) and an irregularly shaped hole inside it with a charge at an arbitrary point, I am asked to find the electric field right outside the conductor sphere. Homework Equations Gauss's law ∫EdA=...

Homework Statement A hollow spherical conductor, carrying a net charge +Q, has inner radius r1 and outer r2=2r1 radius (see the figure ). At the center of the sphere is a point charge +Q/2. A.Write the electric field strength E in all three regions as a function of r: for r>r2,r1<r<r2...

i can't grasp the idea that how is electrostatic induction possible in a conductor. for example, if a negatively charged strip is brought near a metal conductor, the electrons will be repelled to the further end of the conductor thus making the end near the charged rod positively charged...

Hi there, I have lately tried to revisit electronics again after a long hiatus. Unfortunately, I am having trouble with basics (which was originally what helped me to fail my post-school education). I've always been interested in particles and their physics and have spent a bit of time...

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...