Editing Electrical network (section)

==Applying electrical laws==

A number of electrical laws apply to all linear resistive networks. These include:

* [[Kirchhoff's current law]]: The sum of all currents entering a node is equal to the sum of all currents leaving the node.

* [[Kirchhoff's voltage law]]: The directed sum of the electrical potential differences around a loop must be zero.

* [[Ohm's law]]: The voltage across a resistor is equal to the product of the resistance and the current flowing through it.

* [[Norton's theorem]]: Any network of voltage or current sources and resistors is electrically equivalent to an ideal current source in parallel with a single resistor.

* [[Thévenin's theorem]]: Any network of voltage or current sources and resistors is electrically equivalent to a single voltage source in series with a single resistor.

* [[Superposition theorem]]: In a linear network with several independent sources, the response in a particular branch when all the sources are acting simultaneously is equal to the linear sum of individual responses calculated by taking one independent source at a time.

Applying these laws results in a set of simultaneous equations that can be solved either algebraically or numerically.  The laws can generally be extended to networks containing [[electrical reactance|reactances]].  They cannot be used in networks that contain nonlinear or time-varying components.