NETWORKS 1: ECE 09'201'01

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CHAPTER 1

• NETWORKS 1 ECE 09.201.01
• 2 SEPTEMBER 2008 Lecture 1 SECTION
  ONE
• ROWAN UNIVERSITY
• College of Engineering
• Dr Peter Mark Jansson, PP PE
• ASSOCIATE PROFESSOR
• DEPARTMENT OF ELECTRICAL COMPUTER ENGINEERING
• Autumn Semester 2008 - Quarter One

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Welcome to Networks I

• Course Learning Objectives
• Define circuit elements
• Master Ohms Law, Kirchoffs Laws, etc.
• Analyze electrical circuits
• Apply circuit parameters (v, i, r, p, etc.)
• Analyze DC circuits with passive elements
  including resistance, energy storage (C,L)
• Model Build circuits using MatLab
  Mentorgraphics and Breadboards

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What is it?
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What is this?
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(No Transcript)
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Why did primitive peoples build stone circles?
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Our Learning Aids Overview

• Lectures Rowan 239
• Laboratories Rowan Hall Room 204/6 - 221
• One Lab Section Tues 3.15-6.00 pm
• Syllabus/Text (read ahead ch. 1/2)
• Breadboards / Tool Kits
• Computer Tools
• Learning Checks
• Website Email

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Learning Check 1

• List 2 learning objectives of the course
  Networks 1

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Learning Aids

• Required Text
• Introduction to Electric Circuits
• 7th Edition (2006)
• Dorf and Svoboda
• Website
• http//users.rowan.edu/jansson/
• Check your Email regularly (daily)

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Cruise course website

• Website
• http//users.rowan.edu/jansson/autumn08/Networks1
  /index.html

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Learning Check 2

• List 2 learning aids for the course Networks 1
  that you think you will actually use most and
  find most helpful to you

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Learning Evaluation

• Grades
• Tests (3 _at_ 20) 60,
• Assignments (40)
• LECTURE
• In-Class LCs, HW and Participation (20)
• LABS
• Reports, HW, etc. (20)

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How do we learn?

• hearing
• seeing
• reading
• doing
• other?
• Do you think you can learn most everyones name
  (15) in this room in lt10 minutes?
• Lets Experiment.

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Lets stand up.

• put down your pencils .
• for the name game
• NOTE Very important learning aid is each of your
  colleagues

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Learning Check 3

• List 3 names of colleagues that you did not know
  before today

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chapter 1 overview

• history of electricity
• electric circuits and current flow
• systems of units
• voltage
• power and energy
• voltmeters and ammeters
• circuit analysis and design

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Imagine a World with..

• No internet
• No cell phones
• No computers
• No television or video games
• No mass communication (radio, telephone)
• No tall buildings

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Imagine a World with..

• No electricity
• No electronic devices
• No medical technology
• No appliances
• Refrigerators
• Microwaves
• Water heaters
• Air conditioning
• No traffic controls

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That world would be

• Primitive
• Difficult to survive in
• A very hard life

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Learning Check 4

• List 2 important electric technologies that have
  improved the quality of life for human beings on
  Earth

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Electrical Engineers Transformed Society

• Long, long ago in countries far, far away the
  journey began..
• 2367 BC Hoang-Ti in China
• 1110 BC Tchi-nan designed
• 600 BC Etruscans control lightning
• 250 BC Flying Cupid in Dianas temple
• 658 AD Japans first magnetic cars

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Electrical Science Emerges

• 600 AD Attractive power of E-S materials
• 1551 Electricity and Magnetism defined
• 1672 Pointed Conductors
• 1720 Greys Planetarium
• 1746 Atmospheric Electricity discovered
• 1814 Electrical Spectrum detailed
• 1821 First Electric Motor

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Electric Technology

• 1825 First Electromagnet
• 1832 First E-M Induction Generator
• 1837 Telegraph
• 1879 First DC Power System
• 1888 First AC Generator
• 1895 X-rays Discovered
• 1901 Radio

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Quotable Quotes

• Heavier than air flying machines are impossible
• Lord Kelvin Royal Society 1895
• There is no likelihood man can ever tap the
  power of the atom
• Robert Milliken Nobel Laureate Physics 1923

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Discovery continues in 20th century

• AC Electric Grids - 1900s
• Fluorescent Lighting - 1930s
• Computing 1930s
• Television 1940s
• Personal Computing - 1970s
• Internet 1990
• 21st Century ?

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Learning Check 5

• Of the electrical discoveries described in the
  last few slides, which was the most significant
  in terms of impact on modern human society?

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electric circuits current flow

• An electric circuit is an interconnection of
  circuit elements linked together to form a closed
  path so that electric current may flow
  continuously

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Resistor
Battery
Where is ground?
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electric circuits current flow

• Current is the time rate of flow of electric
  charge (q) past a given point
• Use lower case to indicate a time varying current
  and upper case to indicate a constant or direct
  current

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units

• Systeme International dUnites
• Base Units (m, kg, s, A, K, mol, cd)
• Derived Units (J, W, C, V, O, S, F, Wb, H)
• What are base units for Energy (J) and Power (W)?

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voltage

• The voltage across an element is the work
  (energy) required to move a unit positive charge
  from the - terminal to the terminal.

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power

• Power is the time rate of expending energy.
• Power absorbed by an element is positive, Power
  delivered by an element is negative.

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Learning Check 6

• If 6V (volts) is dissipated across a resistor in
  which the current is 2A (amperes) what is the
  power used in watts?

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passive sign convention (psc)

• positive current flows from positive voltage to
  negative voltage.

Is the current in this resistor positive or
negative?
Is the current in this element positive or
negative?
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Learning Check 7

• PSC positive current flows from positive
  voltage to negative voltage.

If i is positive, does this conform with PSC?
If i is positive, does this conform with PSC?
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passive sign convention (psc)

• positive current flows from positive voltage to
  negative voltage.

Is the current in this resistor positive or
negative?
Is the current in this element positive or
negative?
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power and psc

• p v i
• Power is absorbed by an element adhering to the
  passive sign convention (sink)
• Power is supplied by an element not adhering to
  the passive sign convention (source)

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power and psc example

• what is the power absorbed or supplied by the
  element below, when i 4A?
• power 12V x 4A 48 W
• does not adhere to passive sign convention,
• so power is supplied.

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power and psc quiz

• what is the power absorbed or supplied by the
  element below, when i -2A?
• power -12V x -2A 24 W
• does adhere to passive sign convention,
• so power is absorbed.

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power and energy

• p v i
• power voltage current (units watts)
• power is the time rate of expending energy
• energy power time (units Joules w-s)
• energy is the capacity to do work

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power and energy

• energy force x distance
• power energy / time period (secs)

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power and energy example

• a mass of 300 grams experiences a force of 200
  newtons. Find the energy (or work expended) if
  the mass moves 15 cm. Also find the power if the
  move is completed in 10 milliseconds.
• energy force x distance (N m)
• energy 200 x .15 30J
• power energy / second (J/secWatts)
• power 30J/10-2 sec 3000W 3kW

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power and energy quiz

• a Motorola StarTAC cellular phone uses a small
  3.6V lithium ion battery with nominal stored
  energy of 200 joules. For how long will it power
  the phone if it draws a 3-mA current when in
  operation?

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quiz solution

• 200 joules 200 watt-secs
• 3.6 V x 3 mA 1.08 x 10-2 watts
• 200 watt-secs / 1.08 x 10-2 watts
• 18,519 seconds
• 18,519 seconds / 3600 sec/hr
• 5.1 hours

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Learning Check 8

• your iPod shuffle uses a small 3.7V polymer
  lithium battery with stored energy of 11,322
  joules. How many hours will it play tunes if it
  draws 70.81mA current when in operation?

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voltmeters and ammeters

• dc current and voltage measurements are made
  with (analog or digital type) ammeters and
  voltmeters
• voltage measurements are made with red probe ()
  at point a, and black probe (-) at point b

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voltmeters and ammeters

• current measurements require breaking into the
  circuit so the ammeter is in series with the
  current flow
• made with red probe () at point b, and black
  probe (-) at point c

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ideal meters

• ammeters negligible voltage drop through it
• voltmeters negligible current flows into it

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circuit analysis and design

• analysis concerned with the methodological
  study of a circuit to determine direction and
  magnitude of one or more circuit variables (V, A)
  
• problem statement
• situation and assumptions
• goal and requirements
• plan ? act ? verify ? if correct, solved
• if not, plan ? act ? verify ? iterate as needed

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Homework for next Tuesday

• See website for Assignment 1
• show all work for any credit
• Dorf Svoboda, pp. 16-18, pp. 44-45
• Begin Lab HW Assignment 1

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Networks I Section One

• REMINDER
• Lab in Room 204/206 TODAY (TUES)
• ALL LAB TEAMS 3.15 6PM
• Dr. Jansson is Lab Instructor
• ECE Sr. Joseph Gillespie is Lab Assistant
• Email gilles38_at_students.rowan.edu