Alternating Current – Class 12 Physics Notes | Full NCERT Summary with Important Diagrams
⚡️ Chapter 7 – Alternating Current (AC) – Class 12 Physics --- 🔹 What is Alternating Current? Alternating Current (AC): An electric current that changes its magnitude and direction with time. Represented as: I(t) = I_0 \sin(\omega t) = Peak current = Angular frequency --- 🔹 AC vs DC Property Alternating Current (AC) Direct Current (DC) Direction Changes with time Constant Source Generator Battery Transmission Less loss More loss --- 🔹 Peak, RMS, and Average Value 1. Peak Value (I₀, V₀): Maximum value of current or voltage. 2. Root Mean Square (RMS) Value: I_{\text{rms}} = \frac{I_0}{\sqrt{2}}, \quad V_{\text{rms}} = \frac{V_0}{\sqrt{2}} 📌 Important Diagram: Graph of AC waveform showing I vs t --- 🔹 AC through Resistor (R) Voltage and current are in the same phase. 📌 Diagram: Phasor diagram for AC through R --- 🔹 AC through Inductor (L) Current lags voltage by . Inductive reactance: X_L = \omega L 📌 Diagram: Phasor diagram for AC through L --- 🔹 AC throug...