All Questions
23 questions
0
votes
1
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92
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Why does the current flow through a wire if the wire is an equipotential surface? [duplicate]
From what I know, current flows across two points only if there is some potential difference across those two points. If that is the case, why does the current flow through a wire then?
See the ...
0
votes
2
answers
60
views
Current in a two capacitors system in parrallel
I solved this question and I got the values of charges on capacitors in figure B. But my question is charge on capacitors is getting redistributed,but how is it possible when potential difference ...
0
votes
3
answers
121
views
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
0
votes
0
answers
64
views
Charging a single plate of a capacitor does not work
I charged a 100nF capacitor with 12V with a battery, then i disconnect the battery from the capacitor and connect the positive side of the capacitor to ground (which is an electron source) ...
- 35
1
vote
1
answer
288
views
How do you set up Kirchhoff's loop rule for a circuit with a charged capacitor, uncharged capacitor, and resistor?
If I connect a circuit with charged capacitor that has charge $q$ to an uncharged capacitor and resistor, how would I set up a differential equation that can be used to find the time constant? I know ...
0
votes
2
answers
122
views
Can current flow through a capacitor submerged in electrolytes?
Imagine two flat conducting plates (3 x 3), one as the anode and the other as the cathode, submerged into electrolytes (e.g. sea water) and a DC current is applied to this apparatus. Could current ...
- 155
1
vote
3
answers
484
views
Is it necessary that a capacitor stores energy but not charge?
Is it necessary that a capacitor stores charge? The definition of capacitor given in books is that it store electric energy. So is it possible that the capacitor does not store charge but stores ...
- 119
0
votes
0
answers
41
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How to use energy conservation in following case [duplicate]
A capacitor of capacitance C is intially uncharged is connected with a battery of emf ε.Find the heat dissipated in the circuit during charging?How can we apply energy conservation although there are ...
- 79
2
votes
2
answers
171
views
Touching single line of AC Power and charge oscillation in body
If a person touches a single line of AC(Only on the live line, and no where else. Say he/she is hanging on the power line using one hand) as shown in the attached image, Do the ions in his/her body ...
- 23
2
votes
4
answers
14k
views
Is there a physical explanation for why increasing a capacitor's capacitance and the circuit's resistance decrease the capacitor's rate of discharge?
The voltage across a capacitor as a function of time is given by:
$$V=V_ie^{-t/RC}$$
Therefore, increasing the resistance and capacitance increases the time it takes for the initial voltage to drop ...
- 817
1
vote
2
answers
119
views
Why do generators need a complete circuit to move electrons but capacitors do not?
A charged capacitor will shock you if you come too close to it or touch it, and you are connected to the ground. A generator will only generate electricity if it has a complete circuit, it cannot just ...
- 635
1
vote
2
answers
4k
views
Charge flowing through switch when it is closed [closed]
The problem that I'm having is that the initial charges would have been 300 and 600 microcoulomb on the 3 and 6 microfarad capacitors respectively. But when the switch is closed there's some charge ...
- 21
0
votes
4
answers
8k
views
Why do Capacitors discharge?
I understand how capacitors charge and i know they discharge but i am so confused why they discharge. How do they suddenly know when they are full to discharge. I am doing a school report and really ...
- 21
0
votes
1
answer
560
views
How to measure residual charge in capacitor?
I understand how to measure capacitance of capacitor with multimeter but it is possible to measure residual charge of "half-discharged" capacitor?
- 185
1
vote
1
answer
82
views
Are there losses in AC when passing through a capacitor?
A capacitor allows AC to pass through. From what I've read it's caused by the changing electric field in the space between the capacitor plates which causes a change in charge on the other plate of ...
- 1,053
1
vote
1
answer
163
views
How increased current carrying capacity / ampacity affects wire gauge size [closed]
In selecting a suitable wire size for manufacturing:
If I have a material that has the same resistivity and density as Copper, but has a higher current carrying capacity / ampacity for the same ...
- 11
2
votes
2
answers
689
views
Discharging a capacitor
Suppose I have a charged capacitor, meaning there's a voltage (electric potential difference), say, $2V$, between its two plates. We don't know the electirc potential of the individual plates, right? ...
- 205
2
votes
1
answer
89
views
Why there cannot be induction current between plates of capacitor while discharging?
If a capacitor gets charged by induction through the plates, then why there is no induction current between them while discharging instead of displacement current ?
- 147
0
votes
1
answer
148
views
charge on the capacitors
When we connecting a capacitor to a battery of $V$ volts. After it is completely charged, it is disconnected from the battery, and if we connected to another capacitor. In this case, there is no ...
- 23
0
votes
1
answer
5k
views
How does a bulb light up when it's connected in a circuit with an uncharged capacitor and a cell?
Since there is a capacitor, isn't it an incomplete circuit? How does the current flow across the dielectric medium? If a bulb was connected to a cell alone and if there was a break in the wires of the ...
0
votes
3
answers
371
views
(Capacitance of a battery?) Finding the charge accumulated on a rod
We all know the expression for the potential difference across a conducting rod moving through a region with a uniform magnetic field:
$\epsilon = B l v$
Now my question is different. Is it ...
- 138
0
votes
3
answers
5k
views
electron flow in capacitor with dielectric
if I make a circuit with a battery and a capacitor (with a dielectric inside),
how it is possible to get a current in the circuit? If electrons go from
one pole of the battery and they arrive to one ...
- 169
7
votes
2
answers
65k
views
Capacitor circuits with light bulb
Let's say we have a normal circuit with a light bulb, with wires and a battery.
When one places a capacitor in this circuit, how is the light bulb able to light up, even when the capacitor prevents ...
- 561