Derive an expression for the resonant frequency of the circuit shown in Figure P6.74. R C L Figure P6.74 (Recall that we have defined the resonant frequency to be the frequency for which the impedance is purely resistive.)

AC Steady State Power (Chapter 1) Different types of AC power 1. Instantaneous Power [Watts] 2. Average Power (Active Power, Real Power) [Watts] 3. Reactive Power (Imaginary Power) [VAR] 4. Complex Power [VA] 5. Apparent Power [VA] 6. Power Factor Instantaneous Power p(t) [W] Its symbol is p(t) and the unit is Watts [W] p(t) = v(t) • i(t); t = time; v(t) = instantaneous voltage; i(t) = instantaneous current Instantaneous Power can have positive or negative sign depending on the current 1. If current i(t) is entering the device then p(t) is positive and the device is absorbing or dissipating power 2. If current i(t) is leaving the device then p(t) is negative and the device is supplying o