The electric dipole moment is a measure of the separation of positive and negative electrical charges within a system, that is, a measure of the system's overall polarity. The SI units for electric dipole moment are coulomb-meter (C⋅m); however, a commonly used unit in atomic physics and chemistry is the debye (D).
Theoretically, an electric dipole is defined by the first-order term of the multipole expansion; it consists of two equal and opposite charges that are infinitesimally close together, although real dipoles have separated charge.
Homework Statement
Point charges +4.70 and -4.70 are separated by distance 3.90mm, forming an electric dipole.
The charges are in a uniform electric field whose direction makes an angle 37.0 degrees with the line connecting the charges. What is the magnitude of this field if the torque exerted...
Hello, I have this problem. I calculated the dipole energy of a dipole moment in an external field using the equation U_m=\frac{1}{2}\int\vec{A}\vec{J}dr^3=\frac{1}{2} \vec{\mu}.\vec{B} however when the force on a dipole is calculated using \int\vec{J}\times\vec{B}dr^3 the formula...
Homework Statement
Consider a polarised sphere of radius R the polarization is given by
P vector = (ar^2 + b) r hat = ( ar+ b/r) r vector
Where a and b are constantHomework Equations
Find the dipole moment of the sphere
The Attempt at a Solution
I knew that P (polarized)= delta p / delta...
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..
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...
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 my book (Griffith's) there are two different expressions for the induced polarization, namely
P = \frac{N}{\text{volume}}<d>
where <d> is the average of the dipole operator and N the number of atoms. The other expression listed is
P = \text{Re}[\varepsilon_0 \chi E]
where E...
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.
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}\,\...
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...
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...
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...
Reading a book about atomic transitions i really don't understand physically what the book means when it talks about differences between the population lifetime and the dipole lifetime that appear in the coerence part of the density matrix of a 2 or a 3 level system.
I imagine that the...
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.
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...
Homework Statement
The electric potential of a grounded conducting sphere of radius r in a
uniform electric field E_{0}\hat{k}along the z direction is given by
V(r,\theta )=-E_{0}r\cos \theta +\frac{E_{0}R^{3}\cos \theta }{r^{2}}
where r is the distance from the centre of the sphere...
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!
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
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...
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...
Could anyone help me with the following problem?
Ammonia molecule has a dipole moment of 1.47D. Calculate the potential generated by this molecule at a point on a dipole axis at a distance of 52.0 nm from the centre of the dipole. how large will the potential be if an ion of charge...
Homework Statement
A wire is bent into the shape shown in the figure. The semi-circular part has a radius r = 4.00 cm and the rectangular part has a width w = 1.00 cm. A current of 0.300 A runs through the loop. What is the magnitude of the magnetic moment of the loop?
Note: The figure...
Homework Statement
I'm trying to do problem 3.28 in griffith's electrodynamics. The problem statement is, to find the dipole moment of a spherical shell with charge distribution σ = kcosθ
The way I tried to do it was to use the definition of dipole moment, which griffith defines as
P=...
Though this might be absurd, I would seriously like to know the average magnetic dipole of a magnet. For example, you might consider a regular magnet in a remote control car's motors, or any other suggestions too. And I have one more doubt- I know that e.m.f=-d(phi)/dt and phi=integral(B.dS)...
Homework Statement
Two point charges q1 = 2\muC and q2 = -2\muC are placed at r1 = (3,0,0) m and r2 = (0,0,4)m respectively
i) What is the force of q1 (in vector form)?
ii) What is the electric field at the origin?
iii) What is the electric dipole moment of this arrangement (in vector...
Hi.
So, you surround a ferromagnet with a solenoid.
Run current through solenoid to create B field withing.
2 Questions:
1:Why do the magnetic dipole moments in the ferromagnet "align" with the magnetic field of the solenoid? Doesn't lenz's law say that the magnetic field within the...
Yeah it's true, I heard him talking all about it tonight. He said he came up with the theory for it a while ago and he heard of it recently then he knew he was right.
Among other things, he briefly said he connected quantum mechanics and consciousness. Then to top it off he said physicists...
Homework Statement
Given a sphere radius R with surface charge density \rho_s=k\;cos\theta. Find the dipole moment \;\vec p.
Homework Equations
\vec p=\int \vec r'\rho_s \;d a = \int_0^{2\pi}\int_0^{\pi}\vec r' k\;cos\theta\; R^2d\theta\;d\phi
The Attempt at a Solution
To me, \vec r' =...
I have a Nickel cylinder, 5 micron in diameter and 10 micron in length. I know the external field \vec{B} is 80 gauss, what is the formula for the magnetic dipole moment of this cylinder in the field?
Now I only have the formula for magnetic dipole of spheres, which is \mu = \frac{4}{3}\pi...
Hi,
What direction does the electron's total magnetic dipole moment point relative to it's total angular momentum vector L+S? It seems to me that it would point oppositely to J=L+S since the spin magnetic dipole moment and the orbital magnetic dipole moment are both opposite to L and S, but...
I am participating in a reading course on nonlinear optics, which is a little difficult since I haven't had any formal education in quantum mechanics other than the standard introductory solving of Schroedinger's eqn. in 1D. Happily this course takes the semiclassical approach, in which the...
I have been wondering recently about the neutron dipole moment, after looking it up with the limited things available on the internet (to my knowledge anyway :) ) I have a few questions hopefully someone could answer for me. Firstly of the three symmetries, as I understand it, Parity, Charge...
Hi,
I have been wondering about a neutron dipole moment, though hypothetical what symmetries would it be violating, wouldn't it be Parity and Time reversal? If this were to be true, would it therefore make the statement below false and the word "inverted" would imply parity?
"T is the law of...
I'm reading in my organic chemistry text about the structure of alkyl halides, as a background to why certain reactions happen (specifically radical halogenation). In it there's a table of halomethanes, that tells the bond length, bond strength, and dipole moment. It pretty much looks like...
Homework Statement
Can't get to the final equality ( integral = - 4*Pi/3).
Homework Equations
\int_V \mathbf{E }dV = - \int_F \frac{_{\mathbf{p}.\mathbf{e_{r}}}}{r^2}\mathbf{e_{r}}r^{2}d\Omega = \mathbf{p}\frac{-4\pi }{3}
The Attempt at a Solution
Can't find how to get -4Pi/3...
Why is the dipole moment of two electrons equal to zero?
\vec{d} = \sum{q_{i}\vec{r_{i}}}
The distance between them is nonzero and they both have charges. It is not obvious to me why this sums to zero.
Problem:
A dipole consists of charges +q and -q separated by 0.62nm . It is in an electric field 2.6×104 C/N.
What is the work required to rotate the dipole from being oriented parallel to the field to being antiparallel to the field?
Equations:
. 90...
Homework Statement
Calculate each torque of a dipole rotating at 30 degree increments for 180 degrees.
Dipole: s=.55 cm q=+/- 3.7nC
Distance from point charge to axis of dipole = 14.3 cm
point charge = +4.5 nC
So there should be 8 phases and 7 torques (number 4 doesn't have a torque...
Hi,can anyone tell me how to calculute magnitude and direction of the electric dipole moment of a system? If the system is a bit complicated? What kind of formula I suppose to use? \vec{p}=q\vec{d}?
When using k.p theory to calculate the magnitude of the electric dipole moment in semiconductors for band-to-band transitions, the value of the dipole moment is basically fitted to the effective mass of the electron in the conduction band. However, the values turn out to be larger than the...
Hello, I have doubts with this problem, I'm not sure, if my solutión is right, so, here we go
Let's two equal charges with the same charge but opposite signs, positive and negative, in a circle, such a distance between them is constant and equal to diametre of the circle. Both charges, turn...
Homework Statement
Determine the dipole moment, \mathbf{p}, of a sphere of radius R with a uniform volume charge, total Q, with respect to its center. Homework Equations
\mathbf{p}=\int \mathbf{r} \rho(\mathbf{r}) d\tauThe Attempt at a Solution
I know that \mathbf{p}=\mathbf{0}, but I have a...
Dear all
I have done some studies trying to understand the relation between the QCD theta angle and neutron electric dipole moment.
General, the QCD vacuum produces the term
L_{\theta} = \theta g_s^2\: G_a^{\mu\nu} \, G^a_{\mu\nu}
this I can derive! I have studied Srednicki ch 93, Ramond...
simple magnetic dipole moment with impossible field lines? clueless.
Hello,
I'm taking a first year university course in electromagnetism. At a certain point we came upon the torque on a current loop in a uniform magnetic field. There we introduced the magnetic dipole moment \overline{\mu} =...