Register to reply

Kirchhoff's Rules

by sap_54
Tags: kirchhoff, rules
Share this thread:
May11-06, 07:19 PM
P: 5
I understand (or at least thought I did) :D Kirchhoff's rules. When I got to this circuit; however, I got a wee bit confused. The arrows indicate where I placed my three arbitrary currents. When writing equations for the two smaller loops (the ones on the left), I didn't know which current to use for the middle portion (in red). Should I add another current here?
Attached Files
File Type: doc circuit.doc (28.5 KB, 24 views)
Phys.Org News Partner Science news on
New type of solar concentrator desn't block the view
Researchers demonstrate ultra low-field nuclear magnetic resonance using Earth's magnetic field
Asian inventions dominate energy storage systems
Doc Al
May12-06, 01:44 PM
Doc Al's Avatar
P: 41,436
I recommend that you use the branch current method to solve these kinds of problems: Assign each distinct branch its own current. (In this circuit, I see 6 branches.)
May12-06, 01:52 PM
P: 837
When does current change?
A good way to think of current is as water flowing through a pipe. Think of the voltage source as a faucet pumping out water. So what would happen if you had a pipe that forked? The water would reach it and the water would split, a portion going one way and another portion going the other.

A more mechanical way of thinking of it is. Current changes when you have elements in parallel. What is the definition of parallel?
A loose definition is when two elements share start/end nodes.

So if you label all your nodes {A,B,C,...} and then arbitrarily assign a current from node A to B, A to C, ... then you will get your answer.

Register to reply

Related Discussions
Kirchhoff's Rules Introductory Physics Homework 2
Kirchhoff's Rules? Introductory Physics Homework 1
Kirchhoff's rules Advanced Physics Homework 1
Kirchhoff's Rules help Introductory Physics Homework 8
Circuits with Kirchhoff's rules Introductory Physics Homework 11