An ac source of period t and voltage amplitude vmax is connected to a single unknown ideal element that is either a resistor, an 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 the voltage is v = + vmax. at time t = t/2 the current is i = −imax , where imax is the current amplitude. what is the unknown element? an ac source of period and voltage amplitude is connected to a single unknown ideal element that is either a resistor, an inductor, or a capacitor. at time = 0 the voltage is zero. at time = the current in the unknown element is equal to zero and the voltage is = + . at time = the current is = , where is the current amplitude. what is the unknown element?