1. Physics 121: Electricity & Magnetism – Lecture 13 Carsten Denker NJIT Physics Department Center for Solar–Terrestrial Research

2. April 18, 2007Center for Solar-Terrestrial Research LC Oscillations

3. April 18, 2007Center for Solar-Terrestrial Research LC Oscillations (cont.) Damped Oscillation

4. April 18, 2007Center for Solar-Terrestrial Research Alternating Current/Forced Oscillations Whatever the natural angular frequency  of a circuit may be, forced oscillations of charge, current, and potential difference in a circuit always occur at the driving frequency  d. AC: alternating current DC: direct current  d : driving angular frequency

5. April 18, 2007Center for Solar-Terrestrial Research Resistive, Capacitive, & Inductive Load Resistor Capacitor Inductor

6. April 18, 2007Center for Solar-Terrestrial Research Series RLC Circuit

7. April 18, 2007Center for Solar-Terrestrial Research Series RLC Circuit (cont.) Impedance Current amplitude Phase constant Resonance

8. April 18, 2007Center for Solar-Terrestrial Research Power in Alternating–Current Circuits RMS current RMS voltage RMS EMF Average power

9. April 18, 2007Center for Solar-Terrestrial Research Transformers Step–up transformer Step–down transformer Transformation of voltage Transformation of currents Load resistance