Simple circuits

• Bring: ? Demo that current = moving charge (van de graaff, can, string, stand, wires, plate capacitor, lights - flourescent? neon?)
• Notes
  • Batteries
    • Store chemical energy, and can convert to kinetic energy of charge carriers
    • Input / output always at FIXED ΔV
    • Charged = high chemical potential, NOT accumulated charge!
  • Current
    • moving charge carriers
    • I = q passing a point / time
    • Charge does not accumulate at any point (that requires high voltage)
  • Resistors
    • CONDUCTIVE - but dissipate kinetic energy of charge carriers into heat
    • Carbon, or some metal alloys
    • Resistance (greater → more dissipation)
    • While carrying a current, they will have a ΔV
  • Wires
    • Insulated copper
    • Low resistance (ideally none)
    • Low ΔV (ideally none)
  • Series
    • Diagram (resistors A and B)
    • A charge leaving A has nowhere to go but B
  • Parallel
    • Diagram (resistors A and B)
    • One side of A and B is connected by wire
    • Other side is also connected by wire
  • Demo
    • Simple diagram
    • Build
• Lab instructions:
  • Correct voltmeter usage
    • Current...
    • Potential difference...
  • Light bulb observations
    • For a single configuration, compare the brightness of the light bulbs to each other
    • For multiple configurations, compare the brightness in one configuration to the brightness in the next