All Questions
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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 ...
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2
votes
2
answers
80
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I can't seem to figure out a way to compute a gradient without reference coordinates
I'm not sure if this question is better asked here or in Mathematics but here it goes:
I'm studying electric dipoles, and this exercise I'm working on asks for the energy between 2 dipoles, given by $$...
- 23
1
vote
0
answers
2k
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Why is the electric field of an axial quadrupole not the same as the electric field of two axial dipoles, at far distance?
An axial electric quadrupole, made of four inline charges $(+q, -q, -q, +q)$ with opposite charges a distance $a$ apart, and the two $-q$ charges adjacent, has an electric field at a remote point $P$ ...
- 111
2
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2
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1k
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Why does the electric field strength for a dipole go as $1/r^3$? [duplicate]
I've been given the following graphic to help wrap my head around this.
If the potential can be shown to represent a $1/r^2$ relation, then I'm more than happy to accept that the electric field is ...
- 3,200
7
votes
5
answers
8k
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Electric field falls off faster than $\frac{1}{r^2}$ for large distances
An excerpt from a book;
The electric field due to a charge configuration with total charge zero, is not zero; but for distances large compared to the size of the configuration, its field falls off ...
- 493
-1
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2
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3k
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Why does the electric field in a dipole cancel out at distances much larger than the separation of the two charges forming a dipole ($r \gg 2a$)?
The electric field of the electric dipole is not zero. Since the charge $q$ and $–q$ are separated by some distance, the electric fields due to them, when added, do not exactly cancel out.
However, ...
14
votes
3
answers
7k
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Is there an electric field around neutral atoms?
Even if the atom is neutral (equal numbers of protons and electrons), the electrons and nucleus form an electrical dipole, so there is still an electric field around them, even though the total charge ...
- 165
0
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0
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52
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strength of each dipole charge
If I have a two dimensional dipole whose line charges are located on the y axis, I know that the electric flux through a gaussian pill box containing both the charges will be zero, that is
\begin{...
- 647
1
vote
1
answer
93
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Where does the net charge on a hemisphere appear to act from?
I was wondering if, like centre of mass, there is anything called "centre of charge".
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1
vote
1
answer
519
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Potential of a dipole with actual physical extension?
I think everybody here knows the equation that gives the potential of a point like dipole, but how does the field look like if you have e.g. a metal sphere with radius $R$ and a certain dipol moment, ...
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