Question

A generator produces a voltage of v = 240 sin 120t volt, where ‘t’ is the time in seconds. The frequency and rms voltages are

• A. $19Hz170V$
• B. $60Hz,240V$
• C. $19Hz,20V$
• D. $75Hz,40V$

Answer 1

The correct option is A $19Hz170V$

$V=240sin120t$
$\begin{array}{cc}\omega =2\pi n& v_{rms}=\frac{v_0}{\sqrt{2}}\\ 120=2\pi n& =\frac{240}{\sqrt{2}}\\ n=\frac{60}{\pi }=19Hz& =120\sqrt{2}\\ & =170V\end{array}$