Find the time required for $50\,Hz$ alternating current to change its value from zero to maximum value.

The peak value of an alternating e.m.f. $E$ given by $E = E_0 \cos \omega t$ is $10 \ V$ and its frequency is $50 \ Hz$. At time $t = \frac{1}{600} \ s$,the instantaneous e.m.f. is:

An alternating current at any instant is given by $i = [6 + \sqrt{56} \sin (100 \pi t + \frac{\pi}{3})] \ A$. The rms value of the current is . . . . . . . (in $A$)

The frequency of an alternating voltage is $50 \ Hz$. The time taken for the instantaneous voltage to increase from zero to half of its peak voltage is:

An alternating current is given by $I = I_A \sin \omega t + I_B \cos \omega t$. The r.m.s. current will be

The average value of an $A$.$C$. voltage given by $V = V_{m} \sin(\omega t)$ over the time interval $t = 0$ to $t = \frac{\pi}{\omega}$ is: