Physics
posted by Mima on .
A 80.0 Hz generator with an rms voltage of 150 V is connected in series to a 3.20 k ohm resistor and a 3.50 micro farad capacitor. Find the phase angle between the current and the voltage.

f=80 Hz, V=150V, R=3200 Ω, C=3.5•10⁻⁶ F
ω=2πf =2π•80=160π(rad/s)
ω²=1/T² =1/(2π)²LC =>
L=1/(2π ω)²C= ....
X(L) =ωL= ...
X(C) =1/ωC= ...
tan φ=(X(L) –X(C))/R = ... 
Xc = 1/2pi*F*C = 1/(6.28*80*3.5*10^6) =
569 Ohms
Z=RjXc = 3200  j569=3250 Ohms[10.1o]
The negative impedance angle means the
circuit is capacitive and the current leads the applied voltage by 10.1o.
Tan A = Xc/R = 569/3200 = 0.17772
A = 10.1o