The rate at which a capacitor charges or discharges will depend on the resistance of the circuit. Resistance reduces the current which can flow through a circuit so the rate at which the charge flows will be reduced with a higher resistance. This means increasing the resistance will increase the time for the capacitor to charge or discharge.
Capacitive reactance can be thought of as a variable resistance inside a capacitor being controlled by the applied frequency. Unlike resistance which is not dependent on frequency, in an AC circuit reactance is affected by supply frequency and behaves in a similar manner to resistance, both being measured in Ohms.
A capacitor has an infinite resistance (well, unless the voltage gets so high it breaks down). The simplest capacitor is made from two parallel plates with nothing but space in between - as you can guess from its electronic symbol. In a DC circuit, a capacitor acts as an open circuit and does not permit current to pass.
Unlike resistance which has a fixed value, for example, 100Ω, 1kΩ, 10kΩ etc, (this is because resistance obeys Ohms Law), Capacitive Reactance varies with the applied frequency so any variation in supply frequency will have a big effect on the capacitor’s, “capacitive reactance” value.
The following formulas and equations can be used to calculate the capacitance and related quantities of different shapes of capacitors as follow. The capacitance is the amount of charge stored in a capacitor per volt of potential between its plates. Capacitance can be calculated when charge Q & voltage V of the capacitor are known: C = Q/V
The initial current is I0 = emf R I 0 = e m f R, because all of the IR I R drop is in the resistance. Therefore, the smaller the resistance, the faster a given capacitor will be charged. Note that the internal resistance of the voltage source is included in R R, as are the resistances of the capacitor and the connecting wires.