Question

1. A coil has inductance of 0.318H and aresistance of 200V .a capacitor of value 3.18Micro farads is connected in parallel with a coil of a sinusoidal supply of variable frequency.calculate the frequency at which the supply of current and voltage are in phase.

Answer 1

We know that

$X_L=X_c$

$f=\frac{1}{2\pi}\sqrt\frac{1}{LC}$

$f=\frac{1}{2\times3.14}\sqrt\frac{1}{0.318\times3.18\times10^{-6}}$

$f=\frac{994.42}{6.28}=158.34Hz$