DC Circuit Analysis of a Capacitor

DC Circuit Analysis with a Capacitor :

In a DC circuit, if we open up a Capacitor, there will be no change in the circuit. We can analyse the circuit by this way.

If for example 9v passes through the Capacitor from a node, the exact 9v will cross the capacitor without any loss.

An ideal capacitor is wholly characterized by a constant capacitance C, defined as the ratio of charge ±Q on each conductor to the voltage V between them.

                                                                               Q=CV

Because the conductors (or plates) are close together, the opposite charges on the conductors attract one another due to their electric fields, allowing the capacitor to store more charge for a given voltage than if the conductors were separated, giving the capacitor a large capacitance.

Sometimes charge build-up affects the capacitor mechanically, causing its capacitance to vary. In this case, capacitance is defined in terms of incremental changes.

DC Condition :

In a network containing one or more capacitors, in a DC state it means that there are NO CURRENTS flowing through any branches in which a charged capacitor is located. Charged capacitors have voltage but not resistance: V= IR is not applicable since no currents flow THROUGH a capacitor. Voltages also correspond to zero.

                                                                              dv/dt =0