Dipole moment is the electrostatic moment generated by two opposite charges taken together, far away from the charge's locations

learn more… | top users | synonyms

0
votes
0answers
19 views

How to calculate the potential energy of a magnetic dipole (with zero torque)

In the following problem, I would like to know how they arrived at their solution for finding the potential energy of a magnetic dipole (boxed in red). I understand I probably have to use the ...
0
votes
0answers
8 views

What is the work-function of a monolayer metal on a substrate with charge redistribution at the interface?

The work-function on subsrate/metal with nm thick (or above) metal layer generally reveal the intrinsic work-funtion of bulk metal. But what if there is a monolayer thick metal, and there is charge ...
1
vote
1answer
38 views

Find out gradient of electric potential at ${\bf r}$ created by eletric dipole of moment ${\bf p}$ [closed]

Suposing an electric dipole of moment ${\bf p}$ located at the origin which creates an electric potential at ${\bf r}$ given by ...
0
votes
1answer
24 views

Force on a dipole

The force exerted by an electric field on a dipole is : $$(\vec{p}.\vec{\nabla})\vec{E}$$ but how exactly do I develop this ? Is it : $$p_x\frac{\partial E}{\partial x}\vec{e_x} + ...
2
votes
0answers
85 views

Why does the electric dipole moment of the electron tell us about its sphericity? [duplicate]

There are a bunch of experiments that claim to show that the electron is highly spherical by measuring the electron electric dipole moment. See e.g.: ...
0
votes
0answers
44 views

Dipole moment of a specific charge distribution

A negative charge cloud distribute as a ellipsoid and a positive point charge situated at the centre of the ellipsoid.What should be the dipole moment of charge distribution.I mean, if the negative ...
1
vote
1answer
75 views

How could the effective electric dipole interaction be derived

In some papers (e.g. Bernreuther equation (1.4), The electric dipole moment of the electron) you can find the electric dipole interaction defined as $$L_I=-\frac i2 ...
-1
votes
1answer
88 views

What exactly is electric dipole moment & how it works?? and Why Electric Dipole Moment vector's direction is from negative charge to positive charge?

What exactly is electric dipole moment & how it works/used? (don't go into deep mathematical calculations) Please answer the question about the direction with good details. Don't just say that ...
0
votes
1answer
327 views

Force between two point dipoles

What would the force between two parallel point dipoles be? I was thinking of doing it the way force between two point charges is found out, by finding the field and then the force but I am not able ...
0
votes
1answer
47 views

How does An Electric Field Create a Dipole Moment of a Rydberg Atom?

I know that an Rydberg Atom will not usually have a Dipole Moment - as the positive nucleus are surrounded by a negative electron cloud, so there is no uneven charge distribution. However, I also ...
0
votes
0answers
29 views

What does the Equation $E_s = -dF$ mean in terms of a Rydberg Atoms Dipole Moment and its Energy?

Could someone explain what the equation $E_s = -d$•$F$: Where, '$d$' is the Rydberg Atoms Dipole Moment, '$F$' is The Electric Field Strength and '$E_s$' is the Energy of the Rydberg Atom. In terms ...
1
vote
3answers
103 views

What does it mean to say “a paramagnetic material is attracted to an external magnetic field?”

I'm just having a hard time wrapping my head around what actually goes on when a paramagnetic material is exposed to an external magnetic field. I understand that the individual dipoles line up so ...
0
votes
2answers
67 views

Relation between electric field and dipole moment

I want to show the following equality $$\int_{\left|\vec{r}\right|<R}d^3r\vec{E}\left(\vec{r}\right)=-\frac{\vec{p}}{3\epsilon_0}$$ where $\vec{p}$ is the dipole moment of a charge distribution ...
1
vote
0answers
44 views

Divergence in interaction between induced dipoles

Suppose I have two polarizable point-particles 1 and 2 arranged on the z-axis and separated by $r$. Each particle has a dipole moment $\mathbf{p}_i=\alpha \mathbf{E}_i$. If we apply an external field ...
0
votes
2answers
130 views

What is $\delta$ in this formula?

What is $\delta$ in the formula below? How can it be evaluated? Is $P$ the expectation value of $cos\theta$? Source (Influence of Hydrophilic Surface Specificity on the Structural Properties of ...
2
votes
1answer
308 views

Potential energy of a dipole in a uniform electric field convention?

When finding the potential energy of a dipole in a uniform electric field, I was told by my lecturer that the convention is that the potential energy is 0 when the dipole moment and electric field ...
1
vote
0answers
41 views

Dipole charge attractions while one of them is turning around other [closed]

There is a electric dipole which is fixed. So angular momentum isn't conserved. And there is charge $Q$ which has initial velocity $u$. My question is: What is the tangential velocity of the charge ...
1
vote
0answers
43 views

Electric dipole moment(EDM) underlying physics [duplicate]

I read in a physics today paper, The electron can have nonvanishing EDM only if nature violates symmetry under time reversal (T) and under the combined operations of charge conjugation (C), which ...
3
votes
1answer
138 views

Why is a dipole moment called a dipole moment?

The General Formula for a moment is the following one: $$ \vec{M} = \vec{r} \times \vec{F}. $$ However the formula for a dipole moment is this one: $$ \vec{p} = Q \vec{d}. $$ How comes this is still ...
2
votes
1answer
153 views

Why can't microwaves use molecules' dipole moments to cool?

My understanding is that microwaves use the dipole moments of water molecules to heat things. The microwaves resonate with the dipole moment, and add energy to the system. How exactly does the ...
1
vote
2answers
194 views

Interaction energy between dipole and potential

It is known that interaction energy = $-\vec{p}.\vec{E}$ where $\vec{p}$ is dipole moment and $\vec{E}$ is the electric field. I have to calculate the interaction energy of a system whose dipole ...
1
vote
2answers
284 views

Why Does Dipole Moment Depend on Distance?

Why does the dipole moment of an electric dipole of different charges depend on the distance from the origin? Physically, I don't understand why something that measures how much of a dipole something ...
3
votes
2answers
279 views

What is the physical significance of the Dipole Transformation of Maxwell's Equations?

The Question Given Maxwell's equations of the form \begin{align} \bar{\nabla}\times \bar{B} = \dfrac{4\pi}{c} \bar{J} + \partial_0 \bar{E} \\ \bar{\nabla}\times \bar{E} = -\partial_0 \bar{B} \\ ...
0
votes
1answer
121 views

Phase difference between incident plane wave incident on a dipole and radiation fields from dipole

i have an incident plane wave and a dipole, consider that plane wave incident on dipole. at this moment what happens to dipole? We know that after incident of plane wave on dipole, the radiation has ...
8
votes
1answer
242 views

How does the electron electric dipole moment (EDM) depend on supersymmetry?

I have read a recent paper that says that limit on the EDM of the electron has now been measured to 12 times better accuracy. According to that paper, as I understood, there should be a difference in ...
1
vote
0answers
67 views

Why do “virtual states” in Raman spectroscopy have absorbance profiles distinct from either the ground or excited states of an absorbing material?

Do virtual states in Raman spectroscopy have distinct and observable dipoles that can interact with and/or induce dipoles in other molecules (over extremely short femtosecond timescales)? This notion ...
4
votes
1answer
138 views

Integrating Radial Vector Fields

Given a integral $$\int_vd^3{r} \;\vec{r}\;\rho(r)$$ and How do you convert it to spherical coordinate system, noting that $\rho(r)$ is indeed as it is without vector, i.e. it is spherically symmetric ...
2
votes
2answers
3k views

Why potential energy of a dipole in an electric field has a negative sign?

In the following equation $$V = -\mathbf{P}\cdot \mathbf{E}$$ why I have to take Potential Energy as negative. Is there any simple reason behind this ? I am preparing for my high school ...
1
vote
1answer
260 views

(Exercise review) Find the moment of the electric dipole

I have solved an exercise, but the result I have obtined is wrong and I can't understand why. If you can help me, I'll be so grateful. Let's consider a charged cylinder, its radius is equal to R and ...
8
votes
2answers
710 views

No magnetic dipole moment for photon

Electrically neutral particles such as neutrinos can have nonvanishing magnetic dipole moments. Spin-1 particles, e.g., deuterium nuclei, can also have dipole moments. Googling seems to show that the ...
0
votes
1answer
138 views

Electric dipole, error in calculation

Currently I am calculating the dipole moment of a metal sphere in a uniform electric field $E_0$ in z-direction. From here I know that the charge density look at page 15 is given by $ 3 \epsilon_0 ...
1
vote
1answer
901 views

Dipole moment induced in a spherical particle

Consider a spherical metal particle made out of gold. If there is an external charge somewhere near the gold particle, is there a way to calculate the resulting dipole moment that is induced by the ...
1
vote
1answer
140 views

Dipole moment dilemmas

Dipole moment for a couple of charges, say q and -q, separated by a distance 'd' is given by 'qd' But what is for dissimilar magnitudes,say (q and 2q) or (q and -2q)? And are dipole moment defined ...
-1
votes
1answer
353 views

Electric dipole moment, which charge is the $q$ for?

Electric dipole moment says $p = qd$. Which charge does the $q$ equal to?
11
votes
1answer
1k views

In the Lennard-Jones potential, why does the attractive part (dispersion) have an $r^{-6}$ dependence?

The Lennard-Jones potential has the form: $$U(r) = 4\epsilon\left[ \left(\frac{\sigma}{r}\right)^{12} - \left(\frac{\sigma}{r}\right)^{6} \right]$$ The (attractive) $r^{-6}$ term describes the ...
4
votes
6answers
8k views

Why the direction of dipole moment is from negative charge to positive charge?

An electric dipole moment is defined as $p = q\times 2d$. How to understand it physically? Why the direction of the electric dipole moment is from negative charge to positive charge?
0
votes
1answer
423 views

Difference between Non-Polar and Dipole moment $\vec\mu$=0

Is there any difference between a molecule having $\vec\mu=0$ and being Non-Polar?
4
votes
2answers
595 views

Neutron electric dipole moment and $T$ symmetry violation

Our textbook (and other sources I have found) says that non-zero electric dipole moment of neutron would violate $T$ symmetry. They prove this statement by first assuming ...