The equation of the time variation of the potential difference across the plates of the capacitor in the resonant circuit is given as U = 50 * cos (pi * 104 * t) (B). The capacitor is 9 x 10 -7 F. Search: oscillation period; circuit inductance; the variation with time of the current in the circuit; a wavelength corresponding to this contour.

Detailed solution shorthand terms, formulas, laws used in the decision, the withdrawal of the calculation formula and the response.
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