# What is the modulating index of an FM carrier having carrier signal swing of 60KHz and modulating signal frequency of 2KHz

$\begin{array}{1 1}(a)\;2.0\\(b)\;10.0\\(c)\;5.10\\(d)\;20.0\end{array}$

Frequency deviation =$\large\frac{\text{Carrier swing}}{2}$
$\Rightarrow \large\frac{60}{2}$$KHz=30KHz Modulating index=\large\frac{\text{Frequency deviation}}{\text{Modulating frequency}} \Rightarrow \large\frac{30}{2}$$=20$
Hence (d) is the correct option.