$A$ coil has inductance of $0.4 \text{ H}$ and resistance of $8 \Omega$. It is connected to an $AC$ source with peak emf $4 \text{ V}$ and frequency $\frac{30}{\pi} \text{ Hz}$. The average power dissipated in the circuit is (in $\text{ W}$)

$A$ direct current of $4\,A$ and an alternating current of peak value $4\,A$ flow through resistances of $3\,\Omega$ and $2\,\Omega$ respectively. The ratio of heat produced in the two resistances in the same interval of time will be.

If $L$,$C$,and $R$ are the self-inductance,capacitance,and resistance respectively,which of the following does not have the dimension of time?

The phase angle between $e.m.f.$ and current in an $LCR$ series $ac$ circuit is:

In a series $LCR$ circuit,$R = 200 \, \Omega$ and the voltage and frequency of the main supply are $220 \, V$ and $50 \, Hz$ respectively. On taking out the capacitance from the circuit,the current lags behind the voltage by $30^\circ$. On taking out the inductor from the circuit,the current leads the voltage by $30^\circ$. The power dissipated in the $LCR$ circuit is......$W$.

Given below are two statements $:$ one is labelled as Assertion $(A)$ and the other is labelled as Reason $(R).$
Assertion $(A) :$ Choke coil is simply a coil having a large inductance but a small resistance. Choke coils are used with fluorescent mercury-tube fittings. If household electric power is directly connected to a mercury tube,the tube will be damaged.
Reason $(R):$ By using the choke coil,the voltage across the tube is reduced by a factor $\left(R / \sqrt{R^2+\omega^2 L^2}\right)$,where $\omega$ is the angular frequency of the supply,$R$ is the resistance,and $L$ is the inductance. If the choke coil were not used,the voltage across the tube would be the same as the applied voltage. In the light of the above statements,choose the most appropriate answer from the options given below $:$