Correct Answer - Option 3 : 0.775
Concept:
The total transmitted power for an AM system is given by:
\({P_t} = {P_c}\left( {1 + \frac{{{μ^2}}}{2}} \right)\)
Pc = Carrier Power
μ = Modulation Index
Power in side band is given by
\({P_{SB}} = {P_c}\left( {\frac{{{\mu ^2}}}{2}} \right)\)
Calculation:
Side-band power (PSB) = 300 W
Carrier power (PC) = 1000 W
\(\frac{{{P_{SB}}}}{{{P_c}}} = \left( {\frac{{{\mu ^2}}}{2}} \right)\)
\(⇒\frac{{300}}{{1000}} = \left( {\frac{{{\mu ^2}}}{2}} \right)\)
⇒ μ = 0.775
