4.1. Tutorial: Circuit Basics

These notes are meant to accompany an in-class tutorial presentation, and may not necessarily stand alone. For reference, see also Basic Circuits.

4.1.1. Electricity

  • electrons, currents
  • potentials, voltage
  • metaphorical traps

4.1.2. Schematics

  • Notation, common symbols
  • KCL
../_images/294px-KCL_-_Kirchhoff's_circuit_laws.svg.png
  • KVL
../_images/800px-Kirchhoff_voltage_law.svg.png

(Images courtesy of wikimedia.)

4.1.3. Digital Multimeters (DMM)

  • purpose
  • probe locations
  • modes: voltage, resistance, current etc.
  • later: the oscilloscope

4.1.4. Resistance and Ohm’s Law

  • visual guide
../_images/resistor-5.6K.png ../_images/resistor-5600-symbol.png
  • Each resistor follows Ohm’s Law: \(V = i * R\). This idea can be understood in several ways:
    1. a voltage across a resistor will cause a current to flow through it: \(i = V / R\)
    2. a current through a resistor will induce a voltage drop across it: \(V = i * R\)
    3. the resistance is defined by the observed ratio of voltage drop to current flow: \(R = V / i\).
  • an empirical property
  • an engineered property
../_images/resistor-color-code.png