Question

What phase difference is obtained from \[\phi=\tan^{-1}((X_C-X_L)/R)\] when \[X_C=4\,\Omega\], \[X_L=8\,\Omega\], and \[R=3\,\Omega\]?

Options

• \[\phi=-35.4^\circ\]

• \[\phi=53.1^\circ\]

• \[\phi=-53.1^\circ\]

• \[\phi=0^\circ\]

Answer 1

Substitution gives \[\phi=\tan^{-1}((4-8)/3)=-53.1^\circ\]. With this sign convention, the negative phase angle indicates that current lags the source voltage.