1. Nodes and Paths KCL and KVL
Chapter 2-2
Nodes and Paths
KCL and KVL

2. Node
A node: is a point where two or more circuit elements meet.
Kirchhoff’s Current Law (KCL): This law states that the algebraic sum of the currents at a node must be equal to zero.
Our sign convention will be:
Assign a negative sign to a current entering a node
Assign a positive sign to a current leaving a node

3. i i2 i3 i1

4. Find I1, I2, and I3.

5. Closed Path or Loop
A closed path: Starting at an arbitrary node we trace a path through selected circuit elements and return to the original node, without passing through any single point more than once
Kirchhoff’s Voltage Law (KVL): states that for any closed loop in a circuit, the algebraic sum of the voltages around the loop must be equal to zero.

8. Find io and voltage across 50 ohm

9. Find vo using Kirchhoff’s laws and Ohm's law. vs = 10 V

10. Find the value of ia. Given vg = 40 V , Rg = 3 Ω , Ra = 30 Ω , and Rb = 100 Ω

11. Circuits with Dependent Sources

12. Find vo

13. Find vo

14. Find vo

15. What you should know
KCL and KVL
Application of them
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