An alternating current is given by $i = 2 \sin \omega t + 6 \cos \omega t$. The $R.M.S.$ current in amperes is,

$A$ resistance of $20 \Omega$ is connected to an alternating current source of $110 V$. If the frequency of the $A.C.$ source is $50 Hz$,then the time taken by the current to change from its maximum value to the $R.M.S.$ value is

An $AC$ source has a voltage of $220V$ and a frequency of $50\,Hz$. How much time (in $sec$) does it take for the voltage to reach zero from its maximum value?

$A$ resistance of $20 \Omega$ is connected to a source of an alternating potential $V = 200 \sin (10 \pi t)$. If $t$ is the time taken by the current to change from the peak value to rms value,then $t$ is (in seconds).

What are $DC$ signals and $AC$ signals? Why do we prefer an $AC$ signal?

An $ac$ current is represented as $i = 5 \sqrt{2} + 10 \cos \left(650 \pi t + \frac{\pi}{6}\right) \text{ A}$. The $r.m.s$ value of the current is: