Dipole Definition and 796 Threads

I am stuck with considering a problem. I don't even really know where to start so any pointers would be a great help. I am considering a semi-analytic model for some data i have. The situation is looking at how light propogates from a point source in diamond to air. At the surface of the...

Homework Statement Consider the following species in the gaseous state: NF_3, \ BeF_2, \ BCl_3, \ KrF_4 \ and \ SeO^{2-}_4 . Which of them have electric dipole moment? Homework Equations The Attempt at a Solution I tried google, but I can't figure out how to check that..

Hi there. If I wanted to calculate the radiation vector (in z > 0) produced by a short dipole with uniform current Io (+z direction) on a infinite perfect electric conductor (plane z=0), I'd have to apply the images method. So I'd have to calculate the radiation vector produced by two short...

Greetings, I wonder with respect to what coordinates the formulas given for the electric dipole is valid. Also I want to comprehend the difference between pure and physical dipoles and why many books put the origin of the cartesian system they define on the middle point of the electric dipole...

QFT Question: What is meant by "dipole form"? Hello physics people! Probably a very basic question, but here goes. I'm taking a course on QFT based on Ryder. I've heard my professor refer to propagators as having a "polar" or "dipole" form. Things like (k^2 - m^2 + ie)^(-1) For anyone who...

Two permanent magnets are on the table some distance apart and having some arbitrary orientation relative to each other. When we let go of them they will rotate and translate until they stick together. I am looking for suitable equations to model this interaction on a computer. Also, if anyone...

Homework Statement Cosnider two dipoles, p1 oriented along z at the origin, and p2 oriented along x at a distance r in the x - y plane. Given that the torque on a dipole in a field E can be written N = p x E, find the torque on each dipole about its centre. Homework Equations N=pxE , E=...

Homework Statement A point dipole p is at the origin of coordinates, while a point charge q is at position r. Calculate the potential energy U of this system in two ways (a) by treating the dipole as a source and q as a test charge in the dipole field (b) by treating the dipole as a...

Homework Statement A spherical sheet of radius a has surface-charge density which depends on the polar angle θ according to the formula σ(θ)=σ0+σ1cos(θ) Find the total dipole moment Homework Equations pz=∫(dQ)z z=rcosθ The Attempt at a Solution I calculated the 1st dipole...

According to Wikipedia, the source of all knowledge, the LHC contains some 1,232 dipole magnets with an additional 392 quadrupole magnets. What is the difference in function between the two types of magnets? How might the effects of magnetic field gradients contribute to the differences...

Is the magnetic field produced by a single electron an ideal dipole, or does it posses higher-order poles?

Homework Statement The HCl (hydrochloric acid) molecule has a dipole moment of about 3.4x10-30 C.m. The two atoms are separated by about 1.10-10 m. What is the net charge on each atom? What is maximal torque that this dipole will experience in a 5.104 N/C electric field? How much energy one...

Hi, In quantum optics, when we talk about atom field interaction with a classical field and quantized atom, we say that the Hamiltonian has an interaction part of the form \hat{d}.\vec{E} where d is the dipole operator. For a two level atom, the dipole operator has only off diagonal elements...

Homework Statement NOTE: Coordinates are in centimeters. A dipole consists of two point charges: +q = 0.911 μC at (-2.53,0) and -q at (2.53,0). a) Calculate V, the potential created by the dipole at (31.9,82). Homework Equations V = k \frac{q}{r} \\ \\ r_{1} = \sqrt{(x-.0253)^2 +...

Hi The energy U of a magnetic dipole in an external magnetic field is given by U = -\mu \cdot B so the energy is zero when they are perpendicular and maximal when they are antiparallel. This makes very good sense intuitively. Quantum-mechanically we have that \mu = -m_Fg_F \mu_B...

Homework Statement A Hertzian dipole at origin generates a signal in empty space which is detected at a wire loop with position vector; r=(50m)ez Homework Equations Signal is detected by changing magnetic field; B(t)=B0 sin(2∏ft)ex Show it is consistent with the Maxwell's solution to a plane...

Homework Statement Write code to calculate the input impedance on a thin wire antenna using the below form of Pocklington's integral equation. Use Method of moments. Use a pulse as the basis function, point matching and delta-gap generator as the 'source'. Assume the wire is broken up into 7...

In the below figure, I'm supposed to express the z-coordinate of the point P, z', by the angle \theta Does this work out as z' = R\cdot \cos \theta? If so, I can't see why... Please give me a hint on this.

Homework Statement I have a long EM question in which there is a Hertzian dipole at a point (0,0,-100), (unknown orientation) and I am told the equation of the physical magnetic field detected 100m away at the origin of Cartesian coordinates. $$(B_0 \sin (2 \pi f t)\mathbf{e}_x$$, and $$B_0 =...

How does it interact with the magnetic and electric fields of the radio waves while receiving them?

I have been trying to figure out which formula for the relationship between oscillator strength and transition dipole moment is correct. Wiki had the following formula: http://photonicswiki.org/index.php?title=Transition_Dipole_Moment f = 4.703 \times 10^{29} \bar{v} \mu^{2}_{ge}\,\...

I have seen two formulas for a short dipole radiation resistance - according to one it is about 200*(l^2/λ^2) Ω, according to the second about 800*(l^2/λ^2) Ω. Which of these is correct, if any? (Let us consider a resonant short dipole, connected to proper inductance). In particular, I would...

Hi friends. I am so new with Comsol software to design something but I wonder, if it is possible to desing a bending magnet (dipole) and simulate the motions of electrons ? I really would like to do this. Please give me a hand,help me to handle and try to do one together. Best.

There are three compounds: 1.) fulvene 2.) calicene 3.) I don't know the name of the third compound. It looks like calicene except that there is not a double bond inside of the three-membered ring. Anyways, it turns out that fulvene and calicene have unusually large dipole moments...

Hello, I have some questions about Dipole Moment, taken from a General Chemistry textbook, in which they treat Dipole Moment as a scalar. Here is a worked example from this textbook: Homework Statement The dipole moment of HCl is 1.11 D, and the distance between atoms is 127 pm. What is...

This is not a homework question I encountered this while revisiting the Electric Dipoles . First of all if someone explains me why the dipole So in the image above which way should the dipole rotate ? Anti Clock Wise or Clock Wise . What My intuition says is the Energy of a dipole is...

Sometimes I am asked to compute the total dipole moment of a charge configuration. Normally you work with dipole moment per unit volume, so you can find the above by integrating over the entire volume, which is quite easy. I'm curius though, what is the physical interpretation of the total...

Hi, I'm trying to find the input impedance of an OCF dipole and I need a sanity check by one of the more experienced guys here. Now, I have assumed that the voltage and current distribution along the line is always the same, no matter where you feed the antenna at [1]. The radiation resistance...

Homework Statement 4 charges are placed each at a distance 'a' from origin. The dipole moment of the configuration is: a)2qa\hat{j} b)3qa\hat{j} c)2qa[\hat{i}+\hat{j}] d)none Homework Equations The Attempt at a Solution How do i determine dipole moment here when there is...

I am trying to understand the elctric dipole approximation when an atom interacts with an electromagnetic wave. I know that if the size of the atom is much much smaller than the wavelength of the radiation, then the dot product od the wavevector and the position vector becomes constant. I...

Hi friends as all know that the direction of electric dipole moment vector is from negative charge towards the positive charge. I am pretty confuse that this direction is allotted to the dipole moment vector with some reason or just by convention.

Homework Statement Show that the energy of an ideal dipole in an electric field E is given by: U = -p \bullet E Homework Equations The energy required to bring to charges together, their electrostatic energy, is: W = ½ ƩqiV(ri) The Attempt at a Solution Well I want to know what the...

I'm confused about what polarization of a dielectric does to its electrical properties. It is clear to me that polarization causes every little atom to get a tiny dipole moment. A measure of the polarization is therefore P = dipole moment per unit volume. However, what is really a dipole moment...

What is the physical meaning of electri dipole moment? What does it tell us about the dipole? Please don't just throw away mathematical equation (p=qd r_hat); help me to get its physical sense!

Please help me with the attached question. I don't understand how you get from the first line to the second line in (2). (I'm not too familiar with working with cross products and vectors). Also, I don't know how you get (5) from (1) and (2). Any help would be much appreciated. Thanks! :)

Homework Statement Determine the dipole moment for the following charge distributions: 1.5uC each at (0,3), (0,5), where the coordinates are in cm. Homework Equations p=qd The Attempt at a Solution Since the coordinates are (0,3) and (0,5) d is 2cm or 0.02m and q is 1.5uC or...

Homework Statement Determine the effective area (Aeff) for a short dipole with L = λ/60 and λ/2 dipole. If the wires used for dipoles has radii a = 1 cm compare Aeff with the physical area. G(short dipole) = 1.5 G(half wave dipole) = 1.64 Homework Equations Aeff = G* λ2/4*pi The...

Homework Statement How do I show that our equations for the E- and B-fields for the oscillating electric dipole do NOT satisfy Maxwell’s equations? Homework Equations After approximations in retarded potentials, we have our E- and B-field as following: E =...

How do I show that our equations for the E- and B-fields for the oscillating electric dipole do NOT satisfy Maxwell’s equations? After approximations in retarded potentials, we have our E- and B-field as following: E = -ω2μ_{0}p_{0}(4∏r)-1sin(θ)cos[ω(t-\frac{r}{c})]\hat{θ} (Griffiths...

Homework Statement A soft iron ball is fixed a distance d above the pole of a rectangular dipole magnet which is permanently magnetized. What is the force the iron ball feels due to the magnetic field? The dimensions of the dipole magnet are a x a x b, where a < b Homework Equations...

Mathematically,its easy to say that when the distance between the points tends to zero,for the dipole moment to stay finite,the charge should tend to infinity. My question is,how should I interpret it? What is a point dipole physically? Could you give examples? thanks

I am trying to approximate the field of a permanent neodymium magnet as that of a magnet dipole. The magnet in link the below can be modeled by a magnetic dipole of what strength? http://www.magnet4less.com/product_info.php?cPath=11&products_id=123 Thanks in advance!

Homework Statement Hi Whenever I read about the dipole approximation in QM, then the Hamiltonian is given as \hat {V}_{\text{dipole}} = -\mathbf{d}\cdot \mathbf{E} where E is the electric field and d the dipole operator. What I am wondering about is that d is an operator. Is it wrong to...

Homework Statement I am so stuck on this, and would be very thankful for any help! a). Calculate the magnetic dipole moment of a single atom, based on the following model: One electron travels at speed 7.40 × 10^6 m/s in a circular orbit of diameter 2 × 10^-10 m. b). The individual atomic...

Homework Statement Hey all, I want to find the potential due to a point-like (mathematical, not physical) dipole inside and outside of a sphere made of dielectric material with dielectric ε. It's of radius R. Outside the sphere is vacuum.Homework Equations The Attempt at a Solution Inside...

Homework Statement An electric dipole is situated at the origin and points along z. An electric charge is released from rest at a point in the (x,y) plane. Show that it swings back and forth in a semicircular arc about the origin. Homework Equations Electric field of a dipole (coord...

I have attached a diagram. s Three charge are at corners of an triangle. The + and - 5.00*10^-6C charges form a dipole. a) Find the magnitude and direction of the force exerted on the dipole from the -10*10^-6C charge. b) For an axis perepndiculat to the line connected the + and -...

Homework Statement A dipole with ±6.0 μC charges is positioned so that the positive charge is 1.0 mm to the right of the origin and the negative charge is at the origin. How much work does it take to bring a 10.0 μC charge from infinity to a position x = 3.0 mm, y = 0.0 mm? (The value of k...

Could anyone help me in solving this following problem. From the given data, i could calculate the dipole moments of all the disubstituted chlorobenzenes(o-, p- and m- isomers)..but i couldn't calculate the following...I would be thankful if anyone comes up with a needful explanation...thanks...

So I heard the words "current dipole" mentioned in a presentation about modeling the retina and using the ERG (electroretinogram). I understand what an electric dipole means (usually speaking of two point charges with opposite charges). But what exactly is meant by current dipole? All I know is...