The impedance of a circuit,when a resistance $R$ and an inductor of inductance $L$ are connected in series in an $AC$ circuit of frequency $f$ is

$A$ bulb and a capacitor are connected in series to a source of alternating current. If its frequency is increased,while keeping the voltage of the source constant,then

If $L$ and $R$ are respectively the inductance and resistance,then the dimensions of $\frac{R}{L}$ will be

$A$ virtual current of $4 \, A$ and $50 \, Hz$ flows in an $AC$ circuit containing a coil. The power consumed in the coil is $240 \, W$. If the virtual voltage across the coil is $100 \, V$,its inductance will be:

$A$ series combination of resistor $R$ and capacitor $C$ is connected to an $A$.$C$. source of angular frequency $\omega$. Keeping the voltage same,if the frequency is changed to $\frac{\omega}{3}$,the current becomes half of the original current. Then the ratio of capacitive reactance and resistance at the former frequency is

$A$ pure inductor of $25.48 \ mH$ and a pure resistor of $8 \ \Omega$ are connected in series with an $AC$ source of frequency $50 \ Hz$. The phase difference between current $(I)$ and voltage $(V)$ in this circuit is . . . . . . . (in $^{\circ}$)