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As long as you don't exceed the breakdown voltage of the capacitor ... which is marked right on it ... DC voltage on it produces NO current flow through it. Only AC 'appears' to flow through a capacitor, and even that appearance is bogus when you really get down to it.

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Q: What happens to current flow in a capacitive when the DC voltage across the capacitor is approximately equal to the source voltage?
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What happens when a start capacitor fails?

An open circuit, by definition, has no continuity, therefore there is no current flow. A failed capacitor in an open circuit would have absolutely no effect.


What happens when a bypass capacitor is shorted?

The circuit becomes a pure resistance circuit where current and voltage are in phase with each others.


What happens to the time taken for the capacitor to charge and discharge when you increase the resistance in the circuit?

It increases. The time constant of a simple RC circuit is RC, resistance times capacitance. That is the length of time it will take for the capacitor voltage to reach about 63% of a delta step change. Ratio-metrically, if you double the resistance, you will double the charge or discharge time.


Why does a capacitor block DC and not AC?

A capacitor consists of two plates separated from one another by an insulator. These plates are normally thin foil and can be sandwiched around a very thin insulator and wrapped into a small package. Since there is an insulator between the plates, DC connected to the two plates cannot flow as long as you do not exceed the breakdown voltage of the insulator. AC current is a different story. Because the insulator is very thin and the effective plate area is relatively large, a negative charge building up on one plate causes electrons to be repelled from the opposite plate, and as the charge on the first plate reverses and becomes positive, the electrons in the opposite plate are attracted back again. This results in a matching alternating current flow on the opposite side of the capacitor. actually what happens, capacitor provides a reactance to current. Xc= 1/ (2*pi*f*c) ,where pi=3.14, f=frequency , c=capacitance vaue as dc current is independent of frequency so Xc becomes infinite so dc current gets infinite resistance. so it is blocked


Is there any current between two fully charged capacitors?

as far i think,there is no current flowing between two fully charged capacitor.current flow in a capacitor happens until it gets fully charged.if it is fully charged then there is no lack of potential,so no current flow.

Related questions

What happens to current flow in a capacitive circuit in comparison to voltage?

The current leads the voltage by 90degree....


What happens to the current in a circuit as a capacitor charges?

What happens to the current in a circuit as a capacitor charges depends on the circuit. As a capacitor charges, the voltage drop across it increases. In a typical circuit with a constant voltage source and a resistor charging the capacitor, then the current in the circuit will decrease logarithmically over time as the capacitor charges, with the end result that the current is zero, and the voltage across the capacitor is the same as the voltage source.


What happens when current transformer is replaced by a capacitor?

You will end up with no current output on the secondary side of the CT.


What happens if the resistor in RC circuit is removed and the capacitor is directly connected to power supply?

If by power supply you mean a voltage source, it really won't matter that the resistor is removed. The voltage source will provide infinite current, instantly charging the capacitor so that the capacitor's voltage is equal to the source.Alternative AnswerIf you are referring to an a.c. circuit, then a load current will continue to flow with its value being determined by the capacitive reactance of the circuit, and the resulting phase angle will lead the supply voltage be very close to 90 degrees.


What happens when a start capacitor fails?

An open circuit, by definition, has no continuity, therefore there is no current flow. A failed capacitor in an open circuit would have absolutely no effect.


What happens when you apply DC directly to a capacitor?

When you apply DC directly to a capacitor, it charges to the value of the DC potential, and then there is (nearly1) zero current flow through the capacitor. If the capacitance is large enough, though, and the DC source has a low enough impedance, the current flow can be quite substantial, damaging things.The reason the equilibrium current is zero is that a capacitor resists a change in voltage, proportional to current and inversely proportional to capacitance...dv/dt = i/c... which makes the capacitor essentially a high pass filter, and a DC blocker.1 The equilibrium current is "nearly" zero because, in our non-ideal world, every capacitor has some leakage current. Practically, the current is zero - from a purist perspective, it is not.


What happens when a bypass capacitor is shorted?

The circuit becomes a pure resistance circuit where current and voltage are in phase with each others.


What happens when dielectric is a conductor?

Yes possible. As a capacitor even with air as dielectric allows alternating current to pass through the capacitor filled with some material as dielectric would allow current to pass through it


What happens when a capacitor connected across a battery for a long time?

For a long time, The capacitor will be charged to the voltage of the DC battery, the positive side of the capacitor touching the positive terminal of the battery. Not much DC current will conduct, except for some tiny leakage current due to imperfection of the cap. The battery will be drained eventually.


How capacitor works practically?

infact what happens in practical capacitor action that air in between parallel plates of that capacitor it acts as a dielectric medium and leakage current starts flowing, that leakage curent is then being bypassed through a conductance in parallel with the capacitor.But in the ideal case that leakage current can't flow due to infinite resistance which can not be provided practically.


What happens when a capacitor reaches a steady state?

when a capacitor reaches it, it acts as a battery


What happens when a capacitor is connected to a dc supply?

is it ? are you sure ? but i know so many circuit where capacitor is connected with ac supply . still , if u connected a capacitor to dc supply , then : 1. if it is in SERIES with the dc supply , it will block all the dc current as capacitor provides infinite resistance to dc current . application : where u want to block dc current.(simple high pass filter) 2. if it is in PARALLEL with the dc supply , it will not block dc current , but if any ac current comes out from the supply , the ac current will go through the capacitor , as capacitor provides small resistance to ac current. application : a) where u want to block ac current.(simple low pass filter) b) to filter the noise (ac components) of dc supply.