The rms value of conduction current in a parallel plate capacitor is $6.9\,\mu A$. The capacity of this capacitor,if it is connected to a $230\,V$ $AC$ supply with an angular frequency of $600\,rad/s$,will be $....\,pF$.

$L$, $C$ and $R$ are connected in series to an $A.C.$ source. Which one of the following is true? Phase relation between current and voltage is such that

When a pure resistor is connected to an $AC$ source,the phase difference between the voltage and the current through the resistor is (in $^{\circ}$)

$A$ series $LCR$ circuit is subjected to an $AC$ signal of $200 \,V, 50 \,Hz$. If the voltage across the inductor $(L=10 \,mH)$ is $31.4 \,V$,then the current in this circuit is $\qquad$

$A$ $70 mH$ inductor is connected to a $220 V, 50 Hz$ $AC$ supply. The rms value of the current in the circuit is:

An $a.c.$ of frequency $f$ is flowing in a circuit containing only an ideal choke coil of inductance $L$. If $V_0$ and $i_0$ represent peak values of the voltage and the current respectively,the average power given by the source to the choke coil is equal to