Question 373: AC fundamentals

Question

An inductor of $$0.5 \mathrm{~mH}$$, a capacitor of $$20 ~\mu \mathrm{F}$$ and a resistance of $$20 \Omega$$ are connected in series with a $$220 \mathrm{~V}$$ a.c. source. If the current is in phase with the e.m.f. the maximum current in the circuit is $$\sqrt{x} A$$. The value of '$$x$$' is

Accepted Answer

When current is in phase with voltage, we have
$$\begin{aligned}
& \mathrm{Z}=\mathrm{R}=20 \Omega \
& \mathrm{e}_0=\sqrt{2} \mathrm{e}_{\mathrm{rms}}=220 \sqrt{2} \mathrm{~V} \
& \mathrm{i}_0=\frac{\mathrm{e}_0}{\mathrm{Z}}=\frac{220 \sqrt{2}}{20}=11 \sqrt{2} \mathrm{~A} \
& \mathrm{i}_0=\sqrt{242} \mathrm{~A}
\end{aligned}$$

Answer

44

Answer

82

Answer

146

Answer

242

AC fundamentals

An inductor of $0.5 \mathrm{~mH}, a capacitor of 20 ~\mu \mathrm{F} and a resistance of 20 \Omega are connected in series with a 220 \mathrm{~V} a.c. source. If the current is in phase with the e.m.f. the maximum current in the circuit is \sqrt{x} A. The value of 'x$' is

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