All Questions
26
questions
1
vote
1
answer
82
views
Electric potential energy, Electric potential and self-energy of a body
The total work done to bring all the charges constituting a body from infinity to the body one by one is called the electrostatic potential energy of the body. And if I divide the expression of ...
- 69
1
vote
0
answers
60
views
Interpretation of Equation of energy stored in continuous charge distribution [duplicate]
In the book "Introduction to Electrodynamics" by David J. Griffiths, $\boldsymbol\S$ 2.4.3$\blacksquare $ The Energy of a Continuous Charge Distribution, I came across this equation for ...
0
votes
2
answers
286
views
Shouldn't the electric potential energy decrease with separation regardless of whether the charges are positive or negative?
I was revising Electric Fields and it came up that if a positive charge moves in the direction of the electric field (so away from a positive charge), then the electric potential energy will decrease ...
2
votes
0
answers
160
views
What should the electrostatic energy of a continuous charge density be?
Hope this doesn't come off as too pedantic or overinterpreted. I've been working on revisiting electrostatic and electrodynamic energy from first principles, and I have the following stumbling block. ...
- 1,043
1
vote
1
answer
89
views
Energy in electric field of an isolated particle?
I learnt that the energy density of electric field is $\frac{\epsilon_0}2E^2$. However, I'm little confused about how can there be energy associated with an electron in empty space.
How can we have ...
- 23
0
votes
2
answers
438
views
Distribution of interaction energy in electrostatic systems
If we have two electrostatic systems their interaction energy is given by
$$U=\epsilon_0\int\vec E_1\cdot\vec E_2dV\equiv\int\rho_1\phi_2dV\equiv\int\rho_2\phi_1dV$$ Here the integral is over the ...
0
votes
2
answers
100
views
Potential energy for uniform sphere doubt
For a sphere of radius $R$, with electric charge distributed in uniform way $\rho=Q/V$, we have
$$U_e=\dfrac{3K_CQ^2}{5R}$$
However, when substituting the charge $Q=\rho V=\rho 4\pi R^3/3$, we get
$$...
- 6,611
1
vote
2
answers
105
views
Why is the sense of the electric field the one that goes from the highest to the lowest values of an electric potential?
To clarify, what's the reason behind it and why is it not the opposite?
- 13
0
votes
1
answer
38
views
Change in electric potential energy [closed]
I am trying to find the velocity of a charged particle $+q$ as it moves away from a charged shell of charge $+Q$ to a distance of $2R$. I know I need to find the change in electric potential energy ...
- 131
0
votes
1
answer
314
views
Which is the difference between electrostatic potential energy and electrostatic potential stored energy?
here it's written that:
The electrostatic potential energy, $U_E$, of one point charge $q$ at position $r$ in the presence of a point charge $Q$, taking an infinite separation between the charges as ...
- 1,319
0
votes
1
answer
90
views
Charge a conductor dome indefinitely frome the inside
Suppose we have a hollow conducting dome with a small hole from which you can touch the inner surface with, let say, a conducting rod. I make sure that the dome is completely uncharged: it has the ...
- 71
12
votes
8
answers
3k
views
Why is the electrostatic force felt in straight lines?
When two positive charges are kept close, they get repelled in the direction of a line joining both the charges. Why is it so?
Also, why is the repulsion in a straight path?
In both the cases, the ...
- 662
0
votes
0
answers
48
views
Potential energy of a system of three charges question
Two point charges are located on the $x$-axis, $q_{1}=-e$ at $x = 0$ and
$q_{2} = +e$ at $x = a$.
(a) Find the work that must be done by an
external force to bring a third point charge $q_{3} = +e$ ...
0
votes
0
answers
35
views
Potential Energy of two charges which are not fixed
Suppose I have 2 charges (+q and +Q) which remain fixed and are placed at a seperation R. They will have some Potential Energy which is kQq/R.
So I wanted to ask that if the charges are not fixed then ...
- 63
4
votes
1
answer
693
views
Energy Stored in a Configuration of Point Charges
Original Question:
The potential energy stored in a system of $n$ charges is:
$$\frac{1}{2}∑_{i=1}^{n}q_i ∑_{j≠i}^{n}\frac{kq_j}{r_{ij}}=\frac{1}{2}∑_{i=1}^{n}q_i \phi(q_i)$$
In the above, $n$ is ...
- 3,075