All Questions
Tagged with electric-fields dipole
116
questions
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384
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Dielectric constant of crystals: Feynman's mistake?
Feynman mentioned in his lecture that we can, in some way, obtain dielectric constant of crystals by summing up the electric field due to dipoles. For example, equation (11.33) from above link shows ...
- 67
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435
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Doubt in the interaction energy of the dipole in an electric field
Consider a dipole ($\vec{p}$) in an electric field ($\vec E$) making an angle $\theta$ with the field.
We can see that $V_1-V_2=Ed\cos\theta$
In books, the derivation for the interaction energy of ...
- 436
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2
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732
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What does "weak-field limit" mean when it refer to dipole and atomic polarization?
In Griffiths' book, Introduction to Electrodynamics 3rd, problem 4.3,it requires me to find the condition on ρ(r) such that equation $p = αE$ will hold in the weak-field limit. The answer gives $ρ（r）=...
- 13
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142
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Can a dipole keep rotating with increasing angular velocity?
Let's say, we have a dipole and we know if we keep it in uniform electric field it allines it self along the electric field direction.so can we some how make an arrangement to rotate it indefinitely ...
- 50
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2
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What does this variable coefficient represent of electric field of dipole?
$V:=\text{potential at point P}$
$V=\frac{2Qd\cos(\theta)}{4\pi \epsilon_{0}r^{2}}$
$E_{r}=-\frac{\partial V}{\partial r}$
$E_{\theta}=-\frac{1}{r}\frac{\partial V}{\partial \theta}$
The problem for ...
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0
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How to interpret bound charges geometrically?
Conceptually, it makes sense to say that when there is an electric field along $E=E\hat{n}$, then given a polarization $P$, the amount that $P$ aligns with the electric field is simply the dot product ...
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101
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Uniform electric field formation in motional emf induction
Why is the electric field $E$ across the ends of a conducting rod, when it's moved with a uniform velocity $v$ in a magnetic field $B$, uniform? Wouldn't it vary non-linearly, since there are opposite ...
- 256
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358
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Electric field due to a dipole sheet
The potential due to a dipole sheet, $S$, having dipole moment density, $\vec\tau$ (per unit area), is given by
$$
\phi(\mathbf r) = \frac{1}{4\pi\epsilon_0}\int_S\frac{\vec\tau(\mathbf r')\cdot(\...
- 1,951
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109
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Confusion over Gauss' law for an ideal electric dipole
To find the charge density of an ideal electric dipole centred at the origin, I can evaluate the divergence of $\vec{E}(\vec{x})$ which equates to evaluating the laplacian of the potential.
Working ...
user161157
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54
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Would this be divergenceless?
If I were to put two charges of opposing polarity next to each other (a finite distance away but not superimposed on each oter) and would then take the divergence of the whole $E$-field, would that be ...
- 275
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How possible is using complex variables to model the electric field system of a dipole? [duplicate]
If one considera a dipole system, is it possible to model the system using complex variables and if ao, how can we use complex analysis to model it? I have the idea that we can model dipole moment as ...
- 3
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How do I calculate the electric field of a dipole after passing through a collecting lens with a given NA?
How can I make the (far field) electric field of a dipole dependent on the numerical aperture of a collection lense it is passing through?
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2
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253
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A Dipole in an External Electric Field
We can derive that, the potential energy of a dipole in an external electric field is
$$U=-\mathbf{p}\cdot \mathbf{E}$$
And Work done by the field on the dipole is
$$W=\mathbf{p}\cdot\mathbf{E}$$
Here,...
- 27
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168
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Why is an electric dipole neutral overall and still has energy?
We are taught that only charged particles have an electric field in their vicinity and a neutral object does not. But a dipole is neutral overall and still produces an electric field. Why?
- 13
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245
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Do neutrons in a strong electric field show a small dipole behaviour?
As neutrons are neutral an electric field should not attract or repel them. However, as they are composed of a positive and a negative part, called one 'up' and two 'down' quarks, shouldn't those ...
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