A coil of inductance 31-8mH with resistance of 12Ω is connected in parallel with a capacitor across 250 volts,50Hz supply, Determine the value of capacitance if no reactive current is taken from the supply. -

Mumbai University > FE > Sem 1 > Basic Electrical and Electronics Engineering

Marks: 7 M

Year: May 2014

Reactive current is zero. It means, it is a parallel resonance circuit.

$f_r=\dfrac{1}{2 \pi f_rL}\sqrt{\dfrac{1}{LC}-\dfrac{R^2}{L^2}} \\ 50=\dfrac{1}{2 \pi}\sqrt{\dfrac{1}{31.8\times10^{-3}\times C}-\dfrac{12^2}{(31.8\times10^{-3})^2}} \\ C=3.22 \times 10^{-9}F$