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**TOPOLOGY IN CIRCUIT ANALYSIS**

Terminology (Nodes explained)

A __node__
is a point in the circuit where two or more circuit elements join.

The current circuit has seven nodes (points ** a**
to **g**). Observing now the figure below, points **b1** and **b2** are
considered to be the same point as node **b. **The same happens to points **
g1** and **g2** which are considered to be the same point as node **g**.
This is due to the fact that there is no circuit element between these points so
they are not considered as separate nodes and are ignored.

__Essential node__
is a node joining three or more elements.

On the above circuit there are
4 essential nodes (b,c,e,g).