How does a capacitor react with a voltage change?

The flow of electrons “through” a capacitor is directly proportional to the rate of change of voltage across the capacitor. This opposition to voltage change is another form of reactance, but one that is precisely opposite to the kind exhibited by inductors.

What happens when a capacitor is connected to a circuit?

When a capacitor is connected to such a circuit, the capacitor continually charges and discharges as the AC voltage reaches its maximum and minimum values. As the capacitor charges and discharges, the electric current that flows through it is restricted by the internal impedance of the capacitor.

What causes reactance in a capacitor?

Reactance in capacitor is created due to current leading the voltage by 90°. Normally the current and voltage follows Ohm's law and are in phase with each other and vary linearly. This phase difference cause decrease in current through capacitor when voltage across the capacitor increases. This can be proved easily as follows:

What happens when a capacitor is fully charged?

Once the capacitor is “fully-charged” the capacitor blocks the flow of any more electrons onto its plates as they have become saturated. However, if we apply an alternating current or AC supply, the capacitor will alternately charge and discharge at a rate determined by the frequency of the supply.

How does frequency affect a capacitor's reactance?

As the frequency applied to the capacitor increases, its effect is to decrease its reactance (measured in ohms). Likewise as the frequency across the capacitor decreases its reactance value increases. This variation is called the capacitor’s complex impedance.

How does a capacitor work?

A capacitor behaves differently if it is placed in a circuit having a DC source or AC source. The capacitor has the property to oppose sudden changes in voltage. When such abrupt change occurs, it tries to maintain the voltage by supplying the required voltage to the circuit.