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?
$\frac{1}{60} \; s$
$60 \; s$
$\frac{1}{120} \; s$
$\frac{1}{240} \; s$
What is $rms$ ? Write the formula of $rms $ for current ?
The variation of $EMF$ with time for four types of generators are shown in the figures. Which amongst them can be called $AC$ ?
Assertion : Ohm’s law cannot be applied to $a.c$ circuit.
Reason : Resistance offered by capacitor for a.c source depends upon the frequency of the source.
$(a)$ The peak voltage of an $ac$ supply is $300\; V$. What is the $rms$ voltage?
$(b)$ The $rms$ value of current in an ac circuit is $10\; A$. What is the peak current?
In a certain circuit current changes with time according to $i = 2\sqrt t .$ r.m.s. value of current between $t = 2$ to $t = 4s$ will be