All Questions
Tagged with electromagnetism potential-energy
130
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What happens to the potential energy of an electric circuit during a voltage drop?
Is it accurate to say $$ W=\int{Fdx}=\int{EQdx}=\int{\frac{dV}{dx}Qdx}=QV$$
so voltage is like g*h it is a potential field and charge is like mass. We know that the energy flux(vector) is given by the ...
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Why don't we define potential due to a magnetic field?
We define electric potential and gravitational potential and use them quite often to solve problems and explain stuff. But I have never encountered magnetic potential, neither during my study (I am a ...
user243267
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How to find convergence of conditionally convergent series obtained while calculating the electrostatic potential energy of a NaCl crystal?
I was reading Electricity and Magnetism by E M Purcell and there in the first chapter there is an attempt to estimate the electrostatic potential energy of the crystal lattice of a NaCl crystal.
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- 1,147
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Electric Potential Outside of Two Infinite Sheets of Opposite charge density
If you have two infinite sheets of equal but opposite charge density, the electric field outside the sheets will be zero due to cancellation. This led me to initially think that the potential would ...
- 171
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Velocity-dependent potentials and the dissipation function
From this previous question Charge, velocity-dependent potentials and Lagrangian where the citation is shown at the page 22, §1.5 of the book Classical Mechanics of Goldstein, we read that
"an ...
- 2,547
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Two Opposite Point Charges: Infinite Potential Energy?
If I had a fixed point-charge ($q_1$, +) and I placed another free-moving charge ($q_2$, -) some distance away, what is the potential energy between them?
The opposite charges attract drawing $q_2$ ...
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If magnetic force can't do any work, then how can we define a potential?
I am confused about the idea that magnetic forces do no work. If something has a potential, then it has energy and hence can do work. I am using the logic of electric fields for this reasoning. I have ...
- 137
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Potential Drop across Inductor VS Potential drop across Rotating coils in $B$-Field
I was trying to understand the difference between the Back emf generated across Inductor due to change in current and Back Emf Generated across a coil that is rotating in presence of B Field.
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Regarding the definition of the electrical potential energy
Let us say we have two charge positive $q_{1}$ and $q_{2}$ very far away from each other. Suppose also that $q_{1}$ is stuck in its place. If we want to bring them closer to some distance $b$ apart, ...
- 1,292
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Can someone explain how magnetic potential energy can exist even though the field is non-conservative?
$U=-B\cdot \mu$ is defined to be the magnetic potential energy, I saw this in my lecture notes, but we had already talked about the fact that since the work done to move a charge there is path ...
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Does this example contradict Earnshaw's theorem in one dimension?
This is basically a continuation of the post here.
Consider electrostatics in $1$-dimension (say, the $x$-axis). Now consider a positive charge $+q$ located at $x=0$, and two equal negative charges $...
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Optical trapping: factor 1/2 in definition of gradient force and potential energy?
If one consider the original deduction of the gradient forces that is applied to the trapped particle we can find the following:
$$F_{grad}=\frac{1}{4} \alpha \nabla E_0^2(r),$$ where $E_0(r)$ is an ...
- 169
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Potential energy of a charge in a magnetic quadrupole field
I have a charged particle of charge $q$ that moves with velocity $\vec{V}$ from a position $\vec{r}$, inside a magnetic quadrupole field of the form: $$\vec{B}=B_{0}(x,y, -2z)$$
The Lorentz force acts ...
- 103
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Motion of an electron near a proton [closed]
Statement of the problem:
Consider an electron and a proton that are initially at rest separated $a$ meters. Do not take into account the movement of the proton, because its mass is much greater ...
- 163
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How understand the stored energy due to magnetic field? [duplicate]
I'm confusing because in this book1 introduces the magnetic energy as mechanical work done by forced magnetic, but if magnetic force doesn't work, besides do who done work?
Teruo Matsushita - ...
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