Replace the emf+series resistance(s) by the Norton equivalent

[andrewmac]

Homework Statement

Write down the node-voltage matrix equation for the following circuit. Hence find the total power dissipated. (Hint: replace the emf+series resistance(s) by the Norton equivalents.)

Homework Equations

n/a

The Attempt at a Solution

The problem I'm having is that I don't fully understand what is meant by replace the emf+series resistance with the norton equivalent. I have a very weak grasp on norton equivalents, and I'm more comfortable with them when I'm told "with respect to.." and a load resistor. The rest of the problem I'm sure I can do fine but this first part has stumped me. Thanks in advance for any assistance, I really appreciate it.

 

[gneill]

Presumably the idea is to replace the 8V supply and 10Ω resistor, and the 5V supply and its 10Ω resistor, and the 20V supply with its 25Ω and 30Ω resistors with their Norton equivalents, then proceed to write the node-voltage equations, etc.

Think of the voltage supplies with their series resistances as Thevenin models.