Answer
a. 810 V.
b. To double the rms output voltage, double the rotation frequency to 240 rev/s.
Work Step by Step
a. The peak induced emf is calculated from equation 21–5.
$$V_{peak}=NB\omega A$$
We find the rms voltage from the peak induced emf.
$$V_{rms}=\frac{V_{peak}}{\sqrt{2}}=\frac{NB\omega A}{\sqrt{2}}$$
$$V_{rms}=\frac{(550)(0.55T)(2 \pi rad/rev)(120rev/s) \pi(0.040m)^2}{\sqrt{2}}=810V$$
b. To double the rms output voltage, double the rotation frequency to 240 rev/s.
