The current flowing through an ac circuit is given by

$I=5 \sin (120 \pi t) A$

How long will the current take to reach the peak value starting from zero?

What is $rms$ ? Write the formula of $rms $ for current ? 

In a circuit, current varies with time as $i = 2\sqrt t $ . Root mean square value of current for interval $t = 2\,s$ to $t = 4\,s$ is

If an alternating voltage is represented as $E = 141\,sin\, (628\,t),$ then the rms value of the voltage and the frequency are respectively

An alternating voltage is given by : $e = e_1\, \sin \omega t + e_2\, \cos \omega t$. Then  the root mean square value of voltage is given by :-

In an $ac$ circuit $I = 100\, sin \,200$ $\pi t.$ The time required for the current to achieve its peak value will be