1. (a) In the United States, the standard sinusoidal AC household voltage is 120 V (rms), and electric light bulbs are classified according to the rate at which electrical energy is consumed in them at that potential difference. In this problem we consider two old-style incandescent light bulbs, one of 60.0 W and the other of 100 W.
(i) Calculate the resistance of each bulb, specifying clearly which is which.
(ii) What is the equivalent resistance of the bulbs connected in parallel? What peak current Imax will be supplied to the parallel combination by the 120-V rms source?
(iii) If the bulbs are instead connected in series, what will Imax be now? In this case, the power consumed by the 100-W bulb will be how many times that of the 60-W bulb? (Give your answer as a fraction in lowest terms.)
(b) A vacuum-filled parallel-plate capacitor has circular plates of diameter 12.0 cm and a capacitance of 4.38 μF. It is connected in a circuit with a 2.00 H inductor, as shown in the figure at the right. The capacitor is charged to a potential difference of 12.0 volts, and then the switch S is closed at time t = 0.
Taking the Maxwell-Ampere law into account, consider the magnitude of the induced magnetic field between the circular plates of the capacitor at the outer edge of the plates. Find the earliest time t > 0 at which the magnetic field has its largest value, and calculate that value. (In SI units, μo = 4n x 10-7 and εo = 8.85 x 10-12.)