I'm stumped by the following problem. To determine the inductance of a coil used in a research project, a student first connects the coil to a 12.0V battery and measures a current of 0.630 A. The student the connects the coil to a 24.0-V(rms), 60.0-Hz generator and measures an rms current of 0.570 A. What is the inductance? When the coil is hooked up to the battery R = V/I = 12V/0.63A = 19 ohms. I'm not seeing how this comes into play in finding the solution to the problem. Z = impedance. w = radial frequency j = imaginary number L = inductance V = Voltage I = Current w = 2pi(60Hz) = 377 rad/sec I(rms) = V(rms)/Z Z = jwL 0.570A = 24.0V/[jL(377rad/sec)] this isn't right because it produce the right answer. What am I missing? A nudge in the right direction would be greatly appreciated. The answer in the back of the book is 99.6 mH. Thanks.