The $r.m.s.$ voltage of the waveform shown is......$V$

For a domestic $AC$ supply of $220 \ V$ at $50 \ \text{cycles per sec}$, the potential difference between the terminals of a two-pin electric outlet in a room is given by

The instantaneous value of current in an $A.C.$ circuit is $I = 3 \sin \left(50 \pi t + \frac{\pi}{4}\right) \text{ A}$. The current will be maximum for the first time at

In an $a.c.$ circuit,the instantaneous current and $emf$ are represented as $I = I_0 \sin(\omega t - \pi / 6)$ and $E = E_0 \sin(\omega t + \pi / 3)$ respectively. The voltage leads the current by

The peak value of $220 \, V$ of $ac$ mains is ...... $V$.

The r.m.s. voltage of domestic electricity supply is $220 \ V$. Electrical appliances should be designed to withstand an instantaneous voltage of......$V$.