All Questions
13 questions
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How do we correctly handle a power source and a capacitor in parallel?
$\newcommand{\d}{\mathrm{d}}$
Here $V$ is an alternating supply, $R$ is a fixed resistor and $C$ is an capacitor. All components, including the diode, are ideal. Say $V(t)=V_\max\sin\omega t$ - with ...
- 220
0
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3
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121
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Why won't the bulb light? [closed]
Here's what the marking scheme says: "Capacitor gets charged first and acts as an insulator/blocks current".
However, electrons flow from negative to positive, so shouldn't the electrons ...
- 93
2
votes
2
answers
234
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Why can't I observe a voltage between two capacitor plates when only one of the plates is connected to a battery?
Let's say I have a battery and a capacitor that is neutral. Now I connect the battery positive terminal to only one plate of the capacitor. From what I know, there is a potential difference between ...
- 23
1
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3
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111
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I have trouble understanding why two different capacitors should have the same amount of charge on each side of a circuit
There is a rhombus with four different capacitors. There's a voltage between the point $a$ and the point $b$, but there is no voltage between the point $c$ and the point $d$. Apparently, assuming that ...
- 33
0
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2
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86
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Is battery a capacitor that's being continuously charged?
Is it correct to say that a battery is like a capacitor which keeps being charged?
- 282
0
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3
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3k
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Why does the voltage measured across a capacitor increase with time [closed]
The voltage measured across a capacitor increases over time as current flows through the circuit because more charge is accumulated. I thought however that since voltage is defined as energy/coulomb, ...
- 79
0
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2
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668
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Why does the capacitor charge through a resistor?
I was working on a question where there was a circuit and the switch was open, there was one capacitor and one resistor. It said: immediately after the switch is closed, what is the current in the ...
- 220
1
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1
answer
4k
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Why does this lightbulb glow faintly when I thouch it with my hand though it's not connected to the AC-source?
Take a look at these three pictures I made of one of our lightbulbs:
The lightbulb is placed in a fitting which can be put directly in the power socket. In the first picture the bulb is turned loose, ...
-1
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3
answers
63
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Why is this a circuit in parallel if it is topologically different than a parallel circuit
I'm struggling to understand why the left circuit is equivalent to a parallel circuit. I'm trying every deformation in my mind I can think of but I can't seem to get out the second circuit.
Secondly,...
- 236
2
votes
1
answer
2k
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Why is work done against the electric field to move charges to charge a capacitor?
I'm a bit confused as to why there is work done against the electric field when charging a capacitor, as charge is moving from high potential to low potential.
For the sake of this question, I'll ...
- 1,187
0
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2
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4k
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How does increasing the distance between 2 copper plates in a circuit affect the capacitance? [duplicate]
We have been told that the voltage decreases, but not been given a proper explanation by my teacher. Can anyone shed some light on this?
Also, does increasing the distance between the plates of a ...
- 1
0
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1
answer
170
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Voltage and Energy in a capacitor [duplicate]
Well, my first question is related to the energy of the capacitor. Why does the energy of capacitor equals $E=\frac{1}{2}QV$ and not $E=QV$;in other words, why we multiplied it by $\frac{1}{2}$??
My ...
- 756
0
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3
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118
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Capacitor related query
Why does a capacitor charge only upto the voltage of the source? I mean in an r.c. circuit if we have a resistor that is in series with the capacitor then because of the potential drop there will be ...
- 121