All Questions
9
questions
12
votes
5
answers
4k
views
Why do we say that electric potential energy is stored in the electric field?
I have been learning electrostatics and came across capacitors. I don't really get why do we say energy is stored in electric field rather than in the charges upon which we or the battery does work. I ...
- 129
2
votes
1
answer
284
views
Energy stored in a space with electric field is $\tfrac12 \varepsilon E^2$ per unit volume. Why?
I'm a high school student and my book says that once it has been established that a region containing electric field $E$ has energy $\tfrac12 \varepsilon E^2$ per unit volume, the result can be used ...
- 21
31
votes
10
answers
8k
views
How is energy "stored in an electric field"?
My physics teacher told me the statement "The energy of a capacitor is stored in its electric field".
Now this confuses me a bit. I understand the energy of a capacitor as a result of the ...
- 492
0
votes
1
answer
100
views
I am confused on how to think about potential energy stored in capacitors [duplicate]
Energy stored in capacitors is represented by
$$U = \frac{1}{2} QV$$
Now I have heard 2 reasons why there’s a half factor, unlike the general potential energy equation, which is $U = QV$.
Capacitors ...
1
vote
5
answers
273
views
Where is energy in energy density?
I was learning about energy density and it seemed to be defined as the potential energy per unit volume in an electric field
$\frac{dU}{dV} = \frac{1}{2}\epsilon E^2$
But how can just the electric ...
- 59
0
votes
0
answers
250
views
Potential difference in parallel plate capacitors
I calculated the potential gain/difference for these two cases.
And found that, voltage difference would be higher for the parallel plate capacitor (2nd one). So from my understanding, the capacitor ...
0
votes
1
answer
206
views
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
0
votes
1
answer
93
views
What is the distance in between two shells of a spherical capacitor?
I am studying Capacitance for my Physics class. We have been working with parallel-plate capacitors, which I understand perfectly. However, I’ve seen some exercises with spherical and cylindrical ...
- 309
1
vote
2
answers
196
views
Whats the meaning of this equation relating electric field and potential energy?
My electrodynamics teacher was explaining that it is required to apply some energy (or do some work) on charges in order to arrange them in space. When he stated an example about energy in a capacitor ...
- 87