Question

Voltage and current in an AC circuit are given by $V=5\sin \left(100\pi t-\frac{\pi }{6}\right)$ and $I=4\sin \left(100\pi t+\frac{\pi }{6}\right)$

• A. voltage leads the current by $30{}^{\circ }$
• B. current leads the voltage by $30{}^{\circ }$
• C. current leads the voltage by $60{}^{\circ }$
• D. voltage leads the current by $60{}^{\circ }$
• E. current and voltage are in phase

Answer 1

Answer: (C)

Net phase difference between current and voltage
$=\frac{\pi }{6}-\left(-\frac{\pi }{6}\right)=\frac{\pi }{3}=60{}^{\circ }$
Hence, current leads the voltage by
$60{}^{\circ }$ .