- #1

Quincy

- 228

- 0

## Homework Statement

Determine the node voltages, Va and Vb of this circuit:

http://img198.imageshack.us/i/circuitx.jpg/

## Homework Equations

## The Attempt at a Solution

Node a: 3 V - Va/4 + (Va - Vb)/2 = 0

3 - Va/4 + 2Va/4 - 2Vb/4 = 0

3 + Va/4 - 2Vb/4 = 0

--> 12 + Va - 2Vb = 0

Node b: Vb/3 - 4 - (Va - Vb)/2 = 0

2Vb/6 - 4 - 3Va/6 + 3Vb/6 = 0

---> -24 - 3Va + 5Vb = 0

Combining two equations yields:

-24 - 3Va + 5Vb

3(12 + Va - 2Vb)

12 - Vb = 0

**Vb = 12 V**

- 24 - 3Va + 5(12) = 0

**Va = 12 V**

According to the book, my answer is wrong. What am I doing wrong??