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:

$A$ 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 alternating voltage is given by $E = 100 \sin \left(\omega t + \frac{\pi}{6}\right) \text{ V}$. The voltage will be maximum for the first time when $t$ is $(T = \text{periodic time})$:

If $i = t^2$ for $0 < t < T$,then the $r.m.s.$ value of the current is:

An $AC$ current is given by $I = I_{1} \sin \omega t + I_{2} \cos \omega t$. $A$ hot wire ammeter will give a reading of:

In an $A.C.$ circuit,the instantaneous current and $E.M.F.$ are represented as $i = i_0 \sin(\omega t - \frac{\pi}{6})$ and $E = E_0 \sin(\omega t + \frac{\pi}{3})$ respectively. The voltage leads the current by