The voltage and current in an a.c. circuit are given by $V = 8 \sin(50\pi t -π/3) volt$ and $I = 6 \sin (50πt + π/3) A$. The correct phase relationship between voltage and current is
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Current leads the voltage by 120°
Given:
$V = 8 \sin \left( 50\pi t - \frac{\pi}{3} \right)$
$I = 6 \sin \left( 50\pi t + \frac{\pi}{3} \right)$
Phase of voltage: $\phi_V = -\frac{\pi}{3}$
Phase of current: $\phi_I = +\frac{\pi}{3}$
Phase difference:
$\Delta \phi = \phi_V - \phi_I = \left(-\frac{\pi}{3}\right) - \left(+\frac{\pi}{3}\right)$
$\Delta \phi = -\frac{2\pi}{3}$
Thus, current leads voltage by $\frac{2\pi}{3}$ radians ($120^\circ$).
Final Answer: Current leads voltage by $120^\circ$