Question

For an amplitude modulated wave the maximum amplitude is found to be $10\,V$ while the minimum amplitude is found to be $2V$ , the modulation index is

• A. $5$
• B. $0.2$
• C. $\frac{2}{3}$
• D. $\frac{3}{2}$

Answer 1

Answer: (C)

$\frac{2}{3}$

Answer 2

Given, $E_{max} = 10\, V$
$E_{min} = 2\,V$
Now, we know that modulation index
$(m_a) = \frac{E_{max} - E_{min}}{E_{max} + E_{min}}$
$= \frac{10-2}{10+2}$
$= \frac{8}{12}$
$= \frac{2}{3}$