All Questions
20
questions
2
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0
answers
57
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Do neutral atoms have an electric field? [duplicate]
The charge of an atom is the sum of its nuclear charges (protons and electrons). If a atom is neutral, does it mean it does not have an net electric field?
I thought about this a lot, here is some of ...
- 139
0
votes
2
answers
98
views
In Maxwell's equations concerning dielectric materials , does the electric field represent the external electric field or the net electric field?
Let's assume we have dielectric material and we apply an external electric field that acts on it (let's call it Ex ) . As a resault we get dipoles who in turn create another electric field (let's call ...
- 329
2
votes
1
answer
251
views
Electric field of dipole antenna
I have seen that the electric field of a dipole antenna detaches and propagates.
For a section of the detached electric field, will the antenna experience recoil if the detached field moves a charged ...
- 156
0
votes
2
answers
99
views
When deriving work from an uniform electric field and dipole why do we need to integrate it?
If the force is constant in a uniform field wouldn't that mean you dont need to integrate to find work?
user361546
2
votes
1
answer
105
views
What is the $\frac{1}{r^2} $ term in the electric field of a Hertzian dipole equations?
Taking common equation for the electric field of a Hertzian dipole from Wikipedia:
$${\displaystyle {\begin{aligned}E_{\theta }=i{\frac {\zeta _{0}I\delta \ell }{4\pi }}\left({\frac {k}{r}}-{\frac {i}{...
- 155
0
votes
2
answers
462
views
Electrostatic potential of a dipole in a non-uniform field
There are numerous derivations for the potential energy of a dipole in a uniform field as:
$$
U = - \boldsymbol{p}\cdot\boldsymbol{E}
$$
But does this hold also for non-uniform fields? Are there any ...
- 602
0
votes
1
answer
435
views
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
0
votes
1
answer
33
views
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?
- 1
1
vote
2
answers
168
views
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
1
vote
2
answers
123
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Electric field in matter- Bound Charges why the term $\rho_b$ exist?
I am reading the book of Griffiths, Introduction to electrodynamics, and he explains in this chapter about the bound charge densities $\sigma_b$ and $\rho_b$
but I do not understand how is it possible ...
- 555
0
votes
1
answer
133
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Dipole oscillators question from Feynman lectures 1.28-29
I am confused by the Feynman lectures Vol1Ch28-29. In all the pictures, there is an electric dipole oscillating vertically. We're assuming the intensity is $E^2$ and that in the far r limit $E$ ...
- 178
0
votes
2
answers
527
views
Why is dipole potential independent of azimuthal angle?
In the formula for dipole potential in spherical coordinates, there is no dependence on azimuthal angle. I don't see why this is as by varying the azimuthal angle, i.e changing our position on the x y ...
- 1,525
-4
votes
1
answer
95
views
What does $e$, $i$ and $\vec{p}$ mean in this formula? [closed]
I've found a formula to calculate the $\vec{E}$-field vector of a Hertzian dipole in the far field (don't know if that's the correct term) to draw and simulate the field lines.
Link to my source: ...
3
votes
1
answer
3k
views
Dipole Inside Cavity of A Spherical Conductor
Consider the following case:
There is a short electric dipole placed arbitrarily inside a spherical cavity inside a solid,uncharged conducting sphere
We need to find electric field at a point ...
- 257
1
vote
1
answer
530
views
Spherical wavefronts from a linear electric dipole-antenna
We are given the equation
\begin{equation*}
\vec{E}=\hat{u}_\theta\ p_0 \sin{(\theta)}\frac{k^2}{4\pi\varepsilon_0r}\sin{(kr-\omega t)}~,
\end{equation*}
that describes the far field radiated ...
