Capacitance Lecture Notes

  • Q = C * V

  • C = Q/V

    • capacitance DOES NOT depend on charge or voltage

  • Units for Capacitance are Farads

  • Using V = kQ/R → C = kR

    • under CGS units →C = R b/c k = 1

  • Capacitors store electrical energy, inductors store magnetic energy

  • Cylindrical Capacitor

    • Derive E in a cylindrical capacitor

    • Derive V

    • Find C (C = Q/V)

  • Spherical Capacitor

  • Capacitance depends on geometry and the material btwn the two plates

  • E = CV2/2

  • Capacitors in Series

    • Capacitors in series are in the same circuit, the charges on each of the capacitors is the same

      • Qtotal = Q1 = Q2 = Q3

    • Voltage: Total potential is equal to the sum of the potentials on all the capacitors

Dielectrics n shi? 11/18