An ac source of period T and maximum voltage V is connected to a single unknown ideal element that is either a resistor,and inductor,or a capacitor.At time t = 0 the voltage is zero.At time t = T/4 the current in the unknown element is equal to zero,and at time t = T/2 the current is I = -I_max,where I_max is the current amplitude.What is the unknown element? A) a resistor B) an inductor C) a capacitor D) an inductor or a capacitor

Question

Quizplus · Accepted Answer

The unknown element is a capacitor because the current leads the voltage by 90 degrees in a capacitive circuit. At t = 0, the voltage is zero and the current is at its maximum (positive or negative), but since the current is zero at t = T/4, this indicates the current is lagging behind the voltage by a quarter period, characteristic of a capacitive circuit. At t = T/2, the voltage would be at its maximum negative value, aligning with the described current behavior.

An Ac Source of Period T and Maximum Voltage V