Contact Us - Tell A Friend - Free-Ed.Net Home   Bookmark and Share

 

Basic Circuit Analysis
Parallel Circuits

Section 2-4 Power in Parallel Circuits


 

 

Definition

Kirchhoff's Current Law

The algebraic sum of all currents entering and leaving a node in a circuit is equal to zero.

 

This figure shows current I1 entering a node, and currents I2 and I3 leaving it.

If I2 = 2A and I3 = 1A, Kirchhoff's Current Law (and common sense) dictates that the current entering the node is 2A + 1A, or 3A.

 

Examples

1. Complete this current node:

+2 + 6 + Ik = 0

Ik = -6

 

 

 

 

Ans: 6A leaving

2. 25mA and 40mA are entering a 3-branch node. What is the amount and direction of the third current?

Ans: 65mA leaving the node.

3. Complete this current node:

+20 + 15 - 5 + Ik = 0

Ik = -30

Ans: 30ma leaving

 

 

 

 

 

 

David L. Heiserman, Editor

Copyright   SweetHaven Publishing Services
All Rights Reserved

Revised: June 06, 2015