The process by which $ac$ is converted into $dc$ is known as
Purification
Amplification
Rectification
Current amplification
The output sinusoidal current versus time curve of a rectifier is shown in the figure. The average value of output current in this case is
The $r.m.s.$ value of potential difference $V$ shown in the figure is
The peak value of $220 \,volts$ of $ac$ mains is......$volts$
A periodic voltage $V$ varies with time $t$ as shown in the figure. $T$ is the time period. The $r.m.s$. value of the voltage is :-
A current in circuit is given by $i = 3 + 4\, sin\, \omega t$. Then the effective value of current is