7-31.The impedance of the main and auxiliary windings of a 1/3 -hp. 120-V, 60-Hz, capacitor-start motor are given as Z_{m}=(4.6+j 3.8) \Omega \text { and } Z_{a}=(9.6+j 3.6) \Omega Determine the value of the starting capacitance that will cause the main and auxiliary winding currents to be in quadrature at starting.

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