A resistor and capacitor are connected in series across an ac generator. The emf of the generator is given byv(t) = V0 cos ωt, where V0 = 120 V,ω = 120π rad/s, R = 400 Ω , and C = 4.0μF . (a) What is the impedance of the circuit?
(b) What is the amplitude of the current through the resistor?
(c) Write an expression for the current through the resistor.
(d) Write expressions representing the voltages across the resistor and across the capacitor.

Four objects each with charge +2.0×10−7c are located at the corners of a square whose sides are 2.0 m long. part a what quantities can be determined using this information? check all that apply. the electric force on a charged object placed at the center of the square. the mass of each object. the total electric potential energy of the system consisting of the four charged objects. part b find the electric force on a charged object placed at the center of the square.