Answer :
Answer:
(a) XL=580.1 Ω
(b) [tex]I_{rms}=0.87A[/tex]
(c) [tex]V_{rms}=234.43V[/tex]
Explanation:
For part (a)
Since we have given angle α, R and Xc.When the problem says that the source voltage lags the current it means α extends into 4th quadrant and is angle is negative
So
[tex]tan\alpha =\frac{X_{L}-X_{C}}{R} \\X_{L}=R.tan\alpha+X_{C}\\ X_{L}=(205)tan(40.5^{o})+405\\X_{L}=580.1ohms[/tex]
XL=580.1 Ω
For part (b)
We are also given the average power So we can find Irms easily
So
[tex]P_{avg}=I_{rms}^{2}R\\I_{rms}=\sqrt{\frac{P_{avg}}{R} } \\I_{rms}=\sqrt{\frac{155}{205} } \\I_{rms}=0.87A[/tex]
For Part (c)
We can find the Vrms by multiplying current I with impedance Z
So
[tex]V_{rms}=I_{rms}Z\\V_{rms}=(0.87)\sqrt{(205)^{2}+(580.1-405)^{2}}\\V_{rms}=234.43V[/tex]