The discussion revolves around calculating peak EMF in an AC circuit, specifically questioning whether the peak voltage (Vlmax) should be 330V. Participants clarify that when working with AC sources, the RMS voltage is typically used, and the relationship V_peak = √2 * V_rms is emphasized. The original poster confuses the peak voltage definition with the EMF equation, leading to misunderstandings about the circuit's behavior. It is noted that in a series circuit with a resistor and inductor, the peak voltage across components must be less than the supply's peak due to reactance. Understanding these principles is crucial for accurate calculations in AC circuits.