All Questions
5
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Different result when deriving electric force as $dW/dr$ and $-dU/dr$
Work done by electric field, $W$ is the negative of the change in electric potential energy, $U_r$.
$$W=-\Delta U$$
By considering an infinitesimal change in EPE, we can deduce that electric force, $...
- 113
0
votes
0
answers
35
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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
2
votes
2
answers
185
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Electric potential and electric potential energy
I have a simple question about the electric potential and electric potential energy.
The gradient of the electric potential gives us the electric field,
and the gradient of the electric potential ...
- 47
0
votes
1
answer
206
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Relation between the energy of a capacitor and the force it applies [closed]
I have a capacitor with stored energy $U$. I do not understand the relation $\vec{F}=-\vec\nabla U$, where $\vec{F}$ is the force that the capacitor applies on the charge inside it.
- 555
2
votes
4
answers
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Why does electric potential energy decrease, if a negative charge increases in strength?
I had a really quick conceptual question regarding the potential energy of particles of opposite charges. The potential energy can be described by the formula
$$U = \frac{kQq}{r}\,.$$
So I was ...
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