$A$ coil has an inductance of $2 \ H$. The ratio of its reactance,when it is connected first to an $AC$ source and then to a $DC$ source,is

The voltage across a pure inductor is represented by the following diagram. Which one of the following diagrams will represent the current?

$A$ sinusoidal supply of frequency $10 \,Hz$ and $r.m.s.$ voltage $12 \,V$ is connected to a $2.1 \,\mu F$ capacitor. What is the $r.m.s.$ value of current in $mA$?

$A$ capacitor of capacitance $150.0\,\mu F$ is connected to an alternating source of $emf$ given by $E = 36 \sin(120 \pi t) \, V$. The maximum value of current in the circuit is approximately equal to $...... \, A$.

The capacitive reactance of a capacitor $C$ is $X \ \Omega$. Both the frequency of the $A.C.$ supply and the capacitance of the capacitor are doubled. The new capacitive reactance will be:

An $AC$ supply gives $30 \ V$ $rms$ which passes through a $10 \ \Omega$ resistance. The power dissipated in it is ...... $W$.