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AP EAMCET201923 Apr 2019Morning ShiftPhysicsCommunication SystemActual

If (E_c ) and (E_m ) are peak values of carrier and modulating signals, respectively then for (100 % ) modulation,

Options

  1. A(E_c= E_m 2 )
  2. B( E_c^2 2 =E_m^2 )
  3. C(E_ c =E_m )
  4. D(E_c=2 E_m )

Correct answer

C. (E_ c =E_m )

Step-by-step solution

Key idea Modulation index of a modulated signal is ( = E_m E_c ) Where, (E_m ) and (E_c ) are peak values of modulating signal and carrier signal. For (100 % ) modulation, modulation index should be unity. Hence, ( =1= E_m E_c ) ( E_m=E_c ) ( ) The correct option is (c).

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