Chapter 21 - AC Circuits - Learning Path Questions and Exercises - Conceptual Questions - Page 747: 7

At the maximum; $t = 0$ or a $120$ amp current

At the maximum or $t = 0$ or a $120$ amp current. the voltage is zero, because the current leads voltage by $90^\circ$ in the capacitor. When the current is maximized, voltage is $1/4$ of a period behind or zero. They are therefore out of phase.