All Questions
Tagged with electric-fields potential-energy
142
questions
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100
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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
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5
answers
273
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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
1
vote
1
answer
187
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How does a transfer of chemical potential energy occur in a circuit?
I am aware that simple DC circuits use a battery which is connected to several elements. In the case that the element is a resistor, I read that the circuit as a whole is an isolated system for energy ...
- 3,340
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1
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435
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Doubt in the interaction energy of the dipole in an electric field
Consider a dipole ($\vec{p}$) in an electric field ($\vec E$) making an angle $\theta$ with the field.
We can see that $V_1-V_2=Ed\cos\theta$
In books, the derivation for the interaction energy of ...
- 436
4
votes
2
answers
132
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Is there a symmetry between scalar and vector formulas for electrostatic and gravitational potential, potential energy, field and force?
Formulas for electrostatic potential, potential energy, field and force, bearing the subscript 'E':
Electrostatic potential $V_E=\frac{U_E}{q}$
Electrostatic potential energy $U_E=k\frac{q_1\,q_2}{r}...
- 156
0
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1
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64
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Why is the distance where electric field is zero different from the one where potential is zero?
I came across this exercise which says that in an xy plane there are two charges: q1 = q and q1 = -12q, and that q1 is at (0,0) on the plane and q2 at (0,9). I was asked to find the abscissa , which ...
- 13
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1
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38
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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
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1
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314
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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
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6
answers
3k
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WHY is there a negative sign in the formula of potential gradient?
Before you tell me there are a bunch of other similar questions asked as well, hear me out ;(
I'm really confused when it comes to work being done. When you're considering a charge moving from a one ...
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0
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250
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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 ...
3
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2
answers
277
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Help interpreting equipotential line diagram
I immediately understood that this question is about how work done to get a test charge from one equipotential line to another doesn’t depend on the path taken but this diagram seems a little strange ...
- 113
0
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1
answer
90
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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
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2
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531
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Is the (electrostatic) interaction energy always positive, or can it be negative? [duplicate]
We know that work done $W$ to assemble $q_1$,...,$q_n$ point charges is
$$
W = \frac{1}{2} \sum_{i = 1}^{n} q_i V(r_i) \tag{I}
$$
Now for the continous charge distribution with charge density $k$, we ...
- 103
1
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3
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6k
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What is the formula of potential difference and electric potential?
Electric Potential
Question 1. Is $V=W/Q$ or $V=P.E./Q$.
P.E. is electric potential energy
Potential difference
Question 2. Is $\Delta$$V=W/Q$ or $\Delta$$V=$$\Delta$$P.E./Q$.
Question 3. Is there any ...
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12
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8
answers
3k
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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 ...
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