There is a $100\,\Omega$ resistance in an $L-C-R$ $AC$ circuit. An $AC$ $emf$ of $200\,V$ and $\omega = 300\,rad/s$ is applied to this circuit. When only the capacitor is removed,the current lags the voltage by $60^o$. When only the inductor is removed,the current leads the voltage by $60^o$. The current in this $L-C-R$ circuit will be.....$A$

Given below are two statements:
Statement $I$: An $AC$ circuit undergoes electrical resonance if it contains either a capacitor or an inductor.
Statement $II$: An $AC$ circuit containing a pure capacitor or a pure inductor consumes high power due to its non-zero power factor.
In the light of the above statements,choose the correct answer from the options given below:

$A$ $ 100 \,W $ bulb is connected to an $ AC $ source of $ 220 \,V, 50 \,Hz $. Then the current flowing through the bulb is

$A$ resistor $R=300 \Omega$ and a capacitor $C=25 \mu F$ are connected in series with a $50 \ V, \frac{50}{\pi} \ Hz$ $AC$ source. The average power dissipated in the circuit is (in $W$)

The figure shows a system of an inductor and a parallel plate capacitor made of $2$ parallel circular plates of area $A$,filled with a dielectric liquid of dielectric constant $K$. $A$ small leak develops in the capacitor,and the liquid starts to fill the inductor of the same dimensions having $n$ turns per unit length. Find the ratio of the magnitude of the initial reactance to the final reactance of the circuit after the liquid fills the inductor completely.
Given: $\omega^2 A^2 n^2 = c^2$
$\omega \rightarrow$ angular frequency of $AC$
$c \rightarrow$ speed of light
$\mu_r \rightarrow$ relative permeability of the liquid

Answer the following questions:
$(a)$ In any $ac$ circuit, is the applied instantaneous voltage equal to the algebraic sum of the instantaneous voltages across the series elements of the circuit? Is the same true for $rms$ voltage?
$(b)$ Why is a capacitor used in the primary circuit of an induction coil?
$(c)$ An applied voltage signal consists of a superposition of a $dc$ voltage and an $ac$ voltage of high frequency. The circuit consists of an inductor and a capacitor in series. Show that the $dc$ signal will appear across $C$ and the $ac$ signal across $L$.
$(d)$ $A$ choke coil in series with a lamp is connected to a $dc$ line. The lamp is seen to shine brightly. Insertion of an iron core in the choke causes no change in the lamp's brightness. Predict the corresponding observations if the connection is to an $ac$ line.
$(e)$ Why is a choke coil needed in the use of fluorescent tubes with $ac$ mains? Why can we not use an ordinary resistor instead of the choke coil?