Hot wire ammeters are used for measuring

The heat produced in a resistor by an $AC$ current is three times the heat produced by a $2 \, A$ $DC$ current. What is the $rms$ value of the $AC$ current in $A$?

In an $ac$ circuit,the instantaneous voltage $e(t)$ and current $i(t)$ are given by $e(t) = 5[\cos \omega t + \sqrt{3} \sin \omega t] \ V$ and $i(t) = 5[\sin(\omega t + \frac{\pi}{4})] \ A$. Determine the phase relationship between voltage and current.

In an $AC$ circuit,the current is given by $I = 100 \sin(200 \pi t)$. The time required for the current to achieve its peak value will be:

An electric lamp is connected to a $220 V, 50 Hz$ supply. The peak value of the voltage is......$V$.

The mean and $rms$ value of an alternating voltage for a half cycle,as shown in the figure,are respectively: