Chapter 7 discusses alternating current (AC) concepts such as peak and RMS values, reactance, impedance, and LCR series circuits. It covers the operation of AC generators and transformers, power factors in AC circuits, and resonance in LCR circuits, including examples and calculations. The chapter emphasizes the relationship between voltage, current, and resistance in AC circuits, as well as the effects of inductance and capacitance on power dissipation.