Chapter 3. Nodal and Mesh Analysis

Question 1

What is element voltage?

Answer 1

Where we examine the voltage across one specific element

Question 2

What is node voltage?

Answer 2

Where we examine the voltage between two nodes

Question 3

What are the three steps for nodal analysis?

Answer 3

1. Assign a reference node
2. Apply KCL to each non-reference node
3. Use Ohm’s law to express in terms of node voltages

Question 4

How should we solve a system of three or more equations ?

Answer 4

Create a matrix and use Cramer’s Rule

Question 5

What’s a voltage source(dependent or independent) between two non-reference nodes called?

Answer 5

A supernode; we treat the two nodes, the voltage source, and any elements in parallel as one large node

Question 6

What is a constraint equation for a supernode?

Answer 6

After applying KVL to the supernode, we can find an equation relating the two nodes and the source

Question 7

What’s the difference between a loop and a mesh?

Answer 7

a loop is closed path that only passes a node once

a mesh is a loop that does not contain any other loops within it

Question 8

What are the three steps for Mesh Analysis

Answer 8

1. Assign mesh currents to all meshes. (choose a clockwise direction for all)
2. Apply KVL to each mesh.
3. Use Ohm’s Law to express voltage in terms of current

Question 9

If the current source is located on only ONE mesh…

Answer 9

the current for that mesh is defined by the source

Question 10

What’s a current source shared by two meshes called?

Answer 10

A supermesh. We ignore the current source and treat both meshes as one mesh

Question 11

When do we use nodal analysis?

Answer 11

• if we are looking for nodal voltages**
• and if the circuit has many parallel elements, and fewer nodes than meshes

Question 12

When do we use mesh analysis?

Answer 12

• if we are looking for branch or mesh currents **
• and if cicuit has many series connected elements, and fewer meshes than nodes