If the instantaneous maximum voltage is 240 V, what is the RMS value?

To determine the RMS (Root Mean Square) value from the instantaneous maximum voltage, you can use the relationship between the maximum voltage (often referred to as peak voltage) and the RMS voltage for a sinusoidal waveform. The formula for calculating the RMS value from the peak voltage is:

[ V_{\text{RMS}} = \frac{V_{\text{peak}}}{\sqrt{2}} ]

In this scenario, the instantaneous maximum voltage is given as 240 V. By applying the formula:

[ V_{\text{RMS}} = \frac{240 V}{\sqrt{2}} ]

Calculating this provides:

[ V_{\text{RMS}} = \frac{240 V}{1.414} \approx 169.68 V ]

This calculation confirms that the correct answer of approximately 169.68 V aligns with the formula for converting peak voltage to RMS voltage, thereby confirming that this is the correct choice. Understanding this relationship is crucial in power engineering, especially when dealing with AC circuits where such conversions are commonly necessary.