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ac power (alternating current)

it blocks dc power

Many people will say a capacitor can't pass current because they consider Electric current to be the flow of electrons but that's not necessarily the case. In a capacitor current is passed by the building up and dropping of an electric field. DC does not flow for long of course.

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Can you by-pass a capacitor in an electric motor?

You can not by-pass the capacitor in an electric motor. Most are capacitor-start motors which require the capacitor to be operational in order to start. If the capacitor is not working then it will need to be replaced.


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.


Why do you connect a diode in parallel to a capacitor?

1. bec the capacitor not allow the current to pass through it after it has charged & it charged in no time ex:(10^-4 second). 2. because it is necessary to avoid wrong polarity by shorting the terminals of the capacitor and tripping the fuse.


Why capacitor allows ac and not dc?

CAPACITOR BLOCKS DC SUPPLY .THERE ARE MAINLY TWO ANSWERS 1.CAPACITIVE REACTANCE Xc=1/( 2*3.1416*F*C) , HERE THE FREQUENCY OF DC SUPPLY IS ZERO .HENCE THE REACTANCE VALUE IS INFINITY .SO IT BLOCKS THE DC SUPPLY. 2.CURRENT THROUGH A CAPACITOR IS PROPORTIONAL TO THE RATE OF CHANGE OF CURRENT . BUT IN THE CASE OF DC SUPPLY, THE RATE OF CHANGE OF CURRENT IS ZERO. HENCE THE CAPACITOR CURRENT IS ALSO ZERO. H.L.kiran


How do you determine the size of acapacitor in a rectifier circuit?

ANSWER In rectifiers for power supplies, the capacitor size is determined by the allowable ripple on the output. This can be determined by the rate at which the capacitor is drained. Specifically, this rate is the current drawn from the capacitor. Assume a half wave rectifier made from four diodes. For part of the cycle, the output current is supplied by the rectifier diode. This is also when the capacitor is charged. While the rectifier is not supplying current -- when the input waveform has dropped below the output voltage -- the capacitor must supply the current. Then, as the input waveform rises above the capacitor voltage, the rectifier supplies the current to charge the capacitor and the output circuit.

Related Questions

Is it true the alternating current can pass through a capacitor while the direct current cannot pass through?

Yes.


What is use of capacitor?

It blocks direct electrical current allowing alternating current to pass


What is the function of mylar capacitor?

In electronic circuits a capacitor is used to pass AC and block DC.


Can ac pass through capacitor?

AC can pass through a capacitor. The higher the frequency of AC the lower the reactance (like resistance). The current and applied voltage are 90 degrees out of phase the current leading the voltage by this amount.


Does the direct current flows throw capacitor?

Yes and no. A capacitor generally does not pass DC current, except for a small "leakage current", but upon the inital application of a DC voltage, the capacitor will pass current until it reaches the full potential of the applied voltage. The simple answer is no it does not. In fact we use that characteristic to "decouple" one circuit from another in amplifiers for example.


Is it true that an alternating current passing through a capacitor While a direct current can not Explain?

Then I'll try this. Just as V=IR is the fundamental equation relating voltage, current and resistance for a resistor circuit, the following equation relates voltace, current and capacitance for a capacitor: Or, if you are not familiar with that calculus term with the derivative, you can think of it as: I(t) = C * (change of voltage per time) So when you have DC, there is no change of voltage with respect to time, so there is zero current. When you have an AC voltage signal that varies across the capacitor with time, that equation lets you calculate the current that results through the capacitor. A capacitor is two surfaces near each other, but not touching. A direct current "sees" a capacitor as an open switch. It cannot pass through. An alternating current "induces" a charge in a capacitor and can pass through.


Which type of current capacitor can block and which type of current capacitor can store?

In an electronic circuit a capacitor can be used to block direct current. In general a capacitor stores electric charge. The charge in a capacitor is the voltage times the capacitance and that is also equal to the charging current times the time (all quantities in SI units - seconds, volts, amps, coulombs, farads)


Why don't capacitors allow DC current to pass?

A capacitor allows AC (to pass through) because capacitors resist a change in voltage.. The capacitor need change resist in Input signal


Can you use a farad capacitor as a battery capacitor?

No. The large farad capacitors are not designed to pass a lot of current. They are intended for ultra-low current applications such as memory retention in a CMOS type device.


What happened if the capacitor is in line when there is no load?

When there is no load on a circuit with a capacitor in the line, no current will pass. The capacitor, if charged, will remain charged until a load is put on to the circuit at which time it will discharge its designed output voltage.


Can you by-pass a capacitor in an electric motor?

You can not by-pass the capacitor in an electric motor. Most are capacitor-start motors which require the capacitor to be operational in order to start. If the capacitor is not working then it will need to be replaced.


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.