Circuit Nodes and Loops
What is Kirchhoff's Voltage and Kirchhoff's current law
Definition of Kirchhoff's Voltage Law:
- Node: a point where several wires electrically connect
- Symbolized by a dot or circle at the wire crossing
- If wires cross without a dot, then not connected
- Nodes also called junctions
- Typically give nodes a number or letter
- Branches: lines with devices connecting two nodes
- Loop: an independent closed path in a circuit
- There may be several possible closed paths
What is Kirchhoff's Voltage and Kirchhoff's current law
Definition of Kirchhoff's Voltage Law:
- Algebraic sum of the voltage drops around any loop or circuit = 0
- Voltage drops are positive in the direction of the set loop current
- Voltage drops negative when opposite loop current
- Voltage sources positive if current flows out of + side
- Voltage sources negative if current flows into + side
- A loop is an independent closed path in the circuit
- Define a "loop current" along that path
- Real currents may be made up of several loop currents
Kirchhoff's Current Law:
The algebraic sum of currents entering any node (junction) is zero.
NOTE:
- The sign convention
- Currents are positive when they entering the node
- Currents negative when leaving
KCL is called a Continuity Equation: It says current is not created or destroyed at any node.
Kirchhoff's Rules
4/
5
Oleh
Unknown
