Question

1. what is the rms voltage of this sine wave? a 19.11 volts b 21.21 volts c 42.4 volts d 30 volts

Explanation:

Step1: Recall RMS formula for sine - wave

For a sinusoidal voltage waveform with peak voltage $V_{peak}$, the RMS (root - mean - square) voltage is given by $V_{rms}=\frac{V_{peak}}{\sqrt{2}}$.

Step2: Identify peak voltage

From the graph, the peak voltage $V_{peak} = 30$ V.

Step3: Calculate RMS voltage

$V_{rms}=\frac{30}{\sqrt{2}}\approx\frac{30}{1.414}=21.21$ V.

Answer:

B. 21.21 volts