12. The circuit AC consists of a series-connected inductor L, a capacitor C and a resistor R (Fig. A). Define the amplitude value ULCm total voltage across the coil and capacitor, if the amplitude value of the voltage across the resistor UR = 100 V, and the phase shift φ between current and voltage is outside of 30 °.

Detailed solution. Decorated in Microsoft Word 2003. (Target decided to use formula editor)