1. ENGS2613 Intro Electrical Science Week 3 Dr. George Scheets
Read
2.5, 3.1, & 3.2
Problems
2.17, 20, 22, 23, 26, & 27
Quiz #2, 3 February
Analyze a circuit using either KVL or KCL equations
Quiz #1 Available for pickup in ES016 Quiz 1A Scores have been bumped by 1 point
Up to a max score of 10

2. Using Kirchhoff's Current Law
Draw & label current thru every element
Arbitrary direction
Hit each circuit element once (& only once)
Same current? Use same label
Label voltage drops for each element
Passive device (Resistor):
MUST follow current directions
Current into + voltage side, Current out on – voltage side
Active device (Voltage or Current source):
Generally Assume Current exits + side & enters – side
Label voltages at each node
Node = wire at single voltage. Boundary is set by any circuit element.
Write Current Equations, mostly using KCL & Ohm's Law
KCL: Sum of currents entering node = sum of currents exiting
Solve Equations

3. DC Circuit with Resistors
Pause. Look at circuit.
Mark known voltages
Mark known currents
Is it possible to simplify? Worth doing so?
Can you use Ohm's Law?
Have 2 of 3 (V, I, or R)?
Can you use KCL?
Know I's thru a node, except one?
Formally use KCL or KVL
KCL: Write current equations based on Node Current I/O
KVL: Write voltage add/drop equations (ΔV's) based on Current Loops

4. Noted Problem Areas Ohm's Law: V = IR KVL Loop Currents Power
Voltage Drop across a device = Current thru the device * Device's Resistance
Might Help to think of it as ΔV = IR
KVL Loop Currents
= Actual current thru a device if only 1 Loop Current
More than one Loop Current? Actual current = sum of the Loop Currents
Power
Active device: P = VI
Passive device (Resistor): P = VI = I2R = V2/R

5. Transistors Intel's i7 processor has over 1.3 billion transitors.
Source: learn.mikroe.com
& hothardware.com