I'm stumped by the following problem.(adsbygoogle = window.adsbygoogle || []).push({});

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.

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# Finding the Inductance of a coil

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