Lecture 1: Intro & Circuit Variables Nilsson ENG17 (Sec. 2): Circuits I Spring April 1, 2014

Overview Personal Introduction Course Introduction Units Circuit Analysis Voltage & Current Basic Circuit Element Power & Energy 2

Dr. Kyle Montgomery B.S University of Houston 3 Schlumberger M.S Purdue University Ph.D Purdue University –Thesis: Novel Approaches for Wide Bandgap Solar Cells 3

What I do now…besides teach… Advise students Research –Novel solar cells w/compound semiconductors –New materials for lighting, solar cells, and beyond –High speed, high power transistors –Alternative energy storage solutions 4

Philosophy…on teaching…and life Teaching is not confined to classroom time Conceptual understanding is key Life really sucks sometimes…how can I help? 5

Overview Personal Introduction Course Introduction Units Circuit Analysis Voltage & Current Basic Circuit Element Power & Energy 6

ENG17: Circuits 1 Electrical quantities and elements Resistive Circuits Transient and steady-state responses of RLC circuits Sinusoidal excitation and phasors Complex frequency and network functions Power Calculations 7

Course Structure TAs –Yuhao Liu (sub: Akash Anand) –Lu Cai –Chi Van Pham –Wu Yu –Xin Zhao Course Website is: – Smartsite used primarily for grades Also using Piazza 8

Overview Personal Introduction Course Introduction Units Circuit Analysis Voltage & Current Basic Circuit Element Power & Energy 9

SI Units 10

Derived Units 11

Prefixes 12

Examples 13

Overview Personal Introduction Course Introduction Units Circuit Analysis Voltage & Current Basic Circuit Element Power & Energy 14

Big Picture Need justifies design Design specs filter to concept, circuit model, prototype Circuit analysis necessary for foundation 15

Overview Personal Introduction Course Introduction Units Circuit Analysis Voltage & Current Basic Circuit Element Power & Energy 16

Test Charge in a Field 17

Work & Energy 18

Electric Potential Energy 19

Voltage 20

Atom & Conductor in a Field 21

Current 22

Ohm’s Law 23

Water Analogy Water pressure = voltage Water flow = current 24

Overview Personal Introduction Course Introduction Units Circuit Analysis Voltage & Current Basic Circuit Element Power & Energy 25

Ideal Element 26 Passive sign convention

Fundamental Quantities 27 1.Voltage (v) 2.Current (i) 3.Charge (q) 4.Flux (Φ)

Overview Personal Introduction Course Introduction Units Circuit Analysis Voltage & Current Basic Circuit Element Power & Energy 28

Power ≠ Energy Power = Time Derivative of Energy UNITS! –Power in Watts –Energy in Watt-hrs or Joules Positive Power = Power Delivered to Circuit Negative Power = Power Extracted from Circuit 29

Recap Personal Introduction Course Introduction Units Circuit Analysis Voltage & Current Basic Circuit Element Power & Energy 30