Question

A generator produces a voltage that is given by $V=240\sin 120t$, where $t$ is in seconds. The frequency and rms voltage is

• A. $60Hz$ and $240V$
• B. $19Hz$ and $120V$
• C. $19Hz$ and $170V$
• D. $754Hz$ and $70V$

Answer 1

The correct option is C $19Hz$ and $170V$

Rms voltage is given by,

$V_{rms}=\frac{V_0}{\sqrt{2}}=\frac{240}{\sqrt{2}}=170V$

Frequency, $f=\frac{\omega }{2\pi }=\frac{120}{2\pi }=19Hz$