EET 110 – Survey of Electronics Chapter 1 Basics of Electricity

Introduction Electrical Systems –Diagrams Block (system) PictorialSchematic –Components SourcePathControlLoadIndicator

Energy, Work and Power Energy –Kinetic Energy –Potential Energy –Chemical Energy Work –Conversion of Energy Power –Rate at which work is done

Structure of Matter Atom –Mode of Atom –Electrons –Nucleus NeutronsProtons –Orbit –Valence Layer

Electrical Charges Like charges repel Opposites attract Each charge is surrounded by an electrostatic field

Static Electricity A collection of charged particles accumulated on a material Examples –Lightning –Dry Montana effect

Electrical Current Movement of electrons – current flow Potential for electrons to flow – voltage or electrical potential Conductors –Single electron in valence layer Insulator –Full valence layer

Other material Semiconductors –Exactly four electrons in the valence layer Superconductors –The Holy Grail of electronics –No resistance AT ALL

Electrical Circuits Conventional Current Flow Electron flow Charge –1 coulomb = 6.25x10 18 electrons Rate of electron flow –1 Ampere or 1 Amp = 1 Coulomb per second

Electro-Motive Force EMFVoltage Electrical Potential Measured in Volts

Resistance The opposition to current flow Dependent on –Material –Length –Area –Temperature Measured in OHMS The inverse of conductance (Mhos or Siemens)

Formulas Current is given as I Voltage as either V or E Resistance as R

Assignment Read Chapter 2 – complete review questions Locate the web page techsci.msun.edu/strizich/index.html