A current in circuit is given by $i = 3 + 4\, sin\, \omega t$. Then the effective value of current is
$5$
$\sqrt 7 $
$\sqrt {17} $
$\sqrt {10} $
A direct current of $10 \,A$ is superimposed on an alternating current $I=40 \cos \omega t\;( A )$ flowing through a wire. The effective value of the resulting current will be ....... $A$
Find the effective value of current $i = 2\, sin\, 100\pi t + 2cos\,(100\pi t + 30^o)$
For a domestic AC supply of $220 \,V$ at $50 \,cps$, the potential difference between the terminals of a two-pin electric outlet in a room is (in volt) given by
Explain electrical energy when an ac current passes through a resistor.
The frequency of $ac$ mains in India is.......$Hz$