All Questions
16
questions
2
votes
2
answers
227
views
Dipoles as vectors
A triatomic molecule $X_2Y$ has plane structure as shown in figure. Due to difference in electronegativity, charge acquired by each X atom is $q$ and charge on Y atom is $- 2q$. The bond length ...
- 89
0
votes
1
answer
68
views
What's the Lagrangian of an electric dipole in an external electric field?
I took electromagnetism a while ago, but now that I took Lagrangian and Hamiltonian mechanics, this question came up to me when I imagined an electric dipole in the presence of a uniform electric ...
- 9
0
votes
1
answer
223
views
How and why potential energy is stored in a dipole in uniform electric field?
I learnt that potential energy is stored in a dipole in uniform electric field when it is rotated from theta = pi/2 to any other theta, and the magnitude of stored potential energy can be found out by ...
- 33
1
vote
1
answer
102
views
A rigorous derivation of the EOM for a charge in a dipolar field
I've given the following question (and solution) to a class I am TAing for. The question is from Zangwill (Prob 4.5) and, for further reference, Zangwill cites R.S. Jones, American Journal of Physics ...
- 1,095
9
votes
1
answer
922
views
On Problem 2.2 in Griffiths' Introduction to Electrodynamics
In part (a) we were asked to find the electric field at a distance $z$ above the midpoint between two equal charges of magnitude $q$ that are a distance $d$ apart. I obtained the correct answer:
$$\...
- 1,638
1
vote
1
answer
310
views
Electric energy from dipole moment
Conventionally one define electric energy as
$$
U = \frac{1}{2} \int \vec{E}(r') \cdot \vec{E}(r') d^3 x'
$$
where $\vec{E}$ is a Electric field.
And from textbook like Griffith, we know that ...
- 3,622
0
votes
1
answer
662
views
Approximation to the dipole of 2 infinite line charges
This is the question:
2 infinite line charges are located at distance $l$ and charged with linear charge density $\lambda $ and $-\lambda$. Find the electric field and the electric potential away ...
1
vote
2
answers
13k
views
How to calculate the dipole potential in spherical coordinates
I want to calculate the dipole potential in spherical coordinates. I know that the potential can be calculated with
$$ \phi = - \int \mathbf E \cdot\mathrm d\mathbf r,$$
but I don't know the electric ...
- 23
0
votes
4
answers
274
views
How does $E = -\nabla V$ work for a dipole? [closed]
For a dipole, the potential is zero at any point on the perpendicular axis, but the electric field isn't zero along that axis. Now, how do I get $E$ from $V=0$ (at that point/axis) from the relation:
...
-1
votes
1
answer
781
views
Questions about derivation of dipole electric field at axial and equatorial point
Firstly, in derivation of electric field at an axial point due to a dipole we have to determine the Electric field at a point P on the axial. So there are two electric fields acting on this $\text{...
- 113
0
votes
1
answer
151
views
Help with this question (Eletric Fields, Dipole) [closed]
The answer in the textbook in the solutions manual is the following:
I didn't undestand the last step. He said he did a binomial expansion, I just can't figure out! Appreciate any help.
- 237
2
votes
3
answers
2k
views
Why does the Electric Field of a dipole have no $x$ component?
According to the solution $2E\sin(\theta) = E_{net}$.
I understand how the dipole works but I don't understand why the x component would be 0?
- 121
3
votes
1
answer
2k
views
Electric field in space created by intersection of spheres of charge [closed]
I am trying to calculate the electric field in space created by a body assembled by the intersection of 2 spheres.
The upper sphere, its center is at $$\frac{d}{2}\mathbf{\hat{z}}$$ with radius $R$ ...
- 201
0
votes
1
answer
322
views
Finding direction of electric force of 2 particles [closed]
A molecule has its centre P of positive charge situated a distance of 2.8 × 10–10 m from
its centre N of negative charge, as illustrated in Fig.
The molecule is situated in a uniform electric field ...
- 45
3
votes
2
answers
10k
views
Motion of a dipole in an electric field
Assume that we have some non-constant electric field $E(x,t)$ and a point-dipole at a position $q$ with a constant dipole moment $\vec{p}$. How would you describe the time evolution, i.e. the motion ...
- 1,034