Question
For an amplitude modulated wave the minimum amplitude is $3\,V$, while the modulation index is $60 \%$. The maximum amplitude of the modulated wave is $......\,V$
✓
Answer
b
Modulation index $=\frac{A_w}{A_c}=0.6$
Modulation index $=\frac{A_w}{A_c}=0.6$
Minimum amplitude of modulated wav $=A_c-A_w=3$
$\therefore A_c-0.6 A_c=3 \Rightarrow 0.4 A_c=3$
$A_c=\frac{3}{0.4}=\frac{15}{2}=7.5\,V$
$A_w=0.6 A_c=4.5\,V$
$\therefore$ Maximum amplitude $= A _{ c }+ A _{ m }$
$=7.5+4.5=12\,V$
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