Question

The alternating current is given by
$i =\left\{\sqrt{42} \sin \left(\frac{2 \pi}{ T } t \right)+10\right\} A$
The r.m.s. value of this current is$ ......... A.$

Answer 1

$f _{ \text{rms }}^{2}= f _{1 \text{rms }}^{2}+ f _{2 \text{rms }}^{2}$
$=\left(\frac{\sqrt{42}}{\sqrt{2}}\right)^{2}+10^{2}$
$=121 \Rightarrow f _{\text{ rms} }=11 A$