Hot wire ammeters are used for measuring
Both $AC$ and $DC$
Only $AC$
Only $DC$
Neither $AC$ nor $DC$
If a direct current of $'a'$ amp is superimposed with an alternating current $'I = b\,sin \,\omega t',$ then effective value of resulting current is
the reason why do we preferred an $a.c.$ voltage instead of $d.c.$ voltage.
A resistance of $20$ ohms is connected to a source of an alternating potential $V = 220\,sin\,(100\,\pi t)$. The time taken by the current to change from its peak value to r.m.s value is
The peak value of an Alternating current is $ 6$ amp, then r.m.s. value of current will be
What are $DC$ signals and $AC$ signals ? Why do we preferred an $AC$ signal ?