0
What happens to the current in a circuit as a capacitor charges?
Wiki User
∙ 14y ago
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.
Wiki User
∙ 14y ago
Add your answer:
Earn +20 pts
What will happen if two terminals of capacitor are shorted?
When the terminals of a capacitor are connected together, the capacitor will discharge, returning to a zero potential state. Capacitors resist voltage change, meaning that if the capacitor is in a circuit that has zero voltage potential, the capacitor will eventually achieve zero potential. If the capacitor is in a circuit that has a 5 volt potential, the capacitor will seek and attempt to maintain that 5 volt potential (provided that the capacitor is rated at 5 volts or more). In an AC circuit, the capacitor will tend to smooth out the sin wave of the current, resisting change in both directions. In a DC power supply circuit, a capacitor will tend to reduce the voltage "ripple", and if the circuit is designed properly, will provide a smooth DC voltage. Shorting the terminals of a capacitor is effectively what often happens in many circuits; it's not a problem.
What happens when led is connected in series with capacitor?
As the capacitor charges the led will dim until it's minimum operational voltage is reached and it goes out.
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 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 an electric circuit is broken?
Then the current will stop flowing.
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 is the flow of an electrical current in a circuit outside the power source?
Usually a circuit is connected to a power source, which could be a battery or an outlet. When this happens current flows through the circuit. The power supply raises electrical charges through the required potential difference, and then in the circuit the charges flow down the potential gradient giving up their energy.
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.
What will happen if two terminals of capacitor are shorted?
When the terminals of a capacitor are connected together, the capacitor will discharge, returning to a zero potential state. Capacitors resist voltage change, meaning that if the capacitor is in a circuit that has zero voltage potential, the capacitor will eventually achieve zero potential. If the capacitor is in a circuit that has a 5 volt potential, the capacitor will seek and attempt to maintain that 5 volt potential (provided that the capacitor is rated at 5 volts or more). In an AC circuit, the capacitor will tend to smooth out the sin wave of the current, resisting change in both directions. In a DC power supply circuit, a capacitor will tend to reduce the voltage "ripple", and if the circuit is designed properly, will provide a smooth DC voltage. Shorting the terminals of a capacitor is effectively what often happens in many circuits; it's not a problem.
What happens when led is connected in series with capacitor?
As the capacitor charges the led will dim until it's minimum operational voltage is reached and it goes out.
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 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 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 capacitor block direct current?
A capacitor opposes a change in voltage, but it will help to look at both the device and at a circuit up close to see what's going on. Any capacitor is two "plates" separated by a dielectric or insulator. Connect a wire to each plate and you've got the device. In a direct current circuit, the voltage source will cause current flow in only one direction. A common battery is a good example. Let's look further. When a capacitor is connected in a DC circuit and the circuit is energized, the voltage source will want to cause current to flow in only the one direction. In the initial moment when the power is switched on, electrons will flow in the circuit. Electrons will leave the negative terminal of the source and enter the positive terminal. The current flow will travel through the wire, and electrons will "pile up" on one of the plates of the capacitor. As electrons are "piling up" on one plate, their presence there will create an electric field across the dielectric to the other plate. This electric field will cause electrons on that other plate to leave. The capacitor is charging, and the voltage source will, for the first instant of time, think that things are "fine" and current will flow. But as the capacitor charges, current flow drops off, and it eventually stops when the voltage across the plates equals the source voltage. In review, as the DC power is switched on in a circuit with a capacitor in it, current will flow "normally" for the first instant. But as the first electrons arrive on one plate and force them off the other plate, current in the circuit will begin dropping off. The voltage developing across the plates of the capacitor opposes the battery voltage. Eventually the capacitor is charged and all current flow has stopped. There is some math that says something slightly different, but for all practical purposes, the capacitor is considered fully charged in a very short period of time. This will depend on circuit resistance and the ability of the source to deliver current, of course. But that capacitor will, when charged, not "pass" any more current. The voltage across the plates is equal to (an opposing) the source voltage, and no more electrons can get onto the negative plate to force more off the positive plate.
What happens to current in a series circuit?
the current in series will be same..
What happens if the capacitor in fluorescent tube becomes faulty?
There's no effect since the capacitor was already faulty i.e it was like not in the circuit. Install a healthy capacitor because it will improve the power factor of the fluorescent lamp circuit thus reducing energy wasted.
