An alternating voltage $\mathrm{V}(\mathrm{t})=220 \sin 100 \ \pi \mathrm{t}$ volt is applied to a purely resistive load of $50\ \Omega$. The time taken for the current to rise from half of the peak value to the peak value is:
$5 \mathrm{~ms}$
$3.3 \mathrm{~ms}$
$7.2 \mathrm{~ms}$
$2.2 \mathrm{~ms}$
A direct current of $10 \,A$ is superimposed on an alternating current $I=40 \cos \omega t\;( A )$ flowing through a wire. The effective value of the resulting current will be ....... $A$
Which of the following components of a $LCR$ circuit, with $ac$ supply, dissipates energy
A direct current of $5\,A$ is superposed on an alternating current $I =10 \sin \omega t$ flowing through the wire. The effective value of the resulting current will be
In an $A.C.$ circuit, $I_{\text {rms }}$ and $I_{0}$ are related as
A resistance of $20$ ohms is connected to a source of an alternating potential $V = 220\,sin\,(100\,\pi t)$. The time taken by the current to change from its peak value to r.m.s value is