Explanation: The term used to identify an AC voltage that causes the same heating in a resistor as a corresponding DC voltage is **Root Mean Square (RMS)**. AC voltage constantly fluctuates, so its effective heating power isn't simply its peak value or average. The heating effect, or power dissipation, in a resistor is proportional to the square of the voltage or current (P = V²/R or P = I²R). The RMS value represents the "effective" AC voltage that would dissipate the same amount of power as a given DC voltage in a resistive load. It's a way to equate AC to DC in terms of energy transfer and heating. "Cosine voltage" describes the sinusoidal shape of the waveform, not its heating equivalence. "Power factor" relates to the phase difference between voltage and current, indicating the efficiency of power delivery in AC circuits, not a voltage value itself. "Average voltage" for a symmetrical AC waveform over a full cycle is zero, which clearly does not represent its heating capability.