Question

The voltage of an ac supply varies with time (t) as $V=120sin100\pi tcos100\pi t$. The maximum voltage and frequency respectively are

• A. 120 volts, 100 Hz
• B. $\frac{120}{\sqrt{2}}volts,100Hz$
• C. 60 volts, 200 Hz
• D. 60 volts, 100 Hz

Answer 1

The correct option is D 60 volts, 100 Hz

$V=120sin100\pi tcos100\pi t\Rightarrow V=60sin200\pi t{V}_{max}=60Vandv=100Hz$