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In a series L-C-R ac circuit driven at angular frequency 100 rad/s, the component values can be read from the figure. Determine the inductance of the coil and the capacitance of the capacitor.

1. 0.8 H and 150 microF
2. 0.8 H and 250 microF
3. 1.33 H and 250 microF
4. 1.33 H and 150 microF

Correct answer: 0.8 H and 250 microF

Solution

Reading the reactances from the figure and applying X_L = omega L and X_C = 1/(omega C) at omega = 100 rad/s yields L = 0.8 H and C = 250 microF for the standard version of this problem. (Exact numbers depend on the figure, which is not fully reproduced here.)

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