A carrier wave of peak voltage 14 V is used to transmit a message. What should be the peak voltage of the modulating signal in order to have a modulation index of 70%?
9.8 V
The modulation index (m) in amplitude modulation is given by:
m = Vm / Vc,
where Vm is the peak voltage of the modulating signal, and Vc is the peak voltage of the carrier wave.
Given m = 70% = 0.7 and Vc = 14 V, we solve for Vm:
Vm = m × Vc = 0.7 × 14 = 9.8 V.
Thus, the correct answer is (c).
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A carrier wave of peak voltage 14 V is used to transmit a message. What should be the peak voltage of the modulating signal in order to have a modulation index of 70%?
Match List - I with List - II
List-I List-II (A) Range (I) Range of frequencies over which communication system works (B) Band width (II) The largest distance between transmitter and receiver (C) Attenuation (III) Loss of strength of a signal during propagation (D) Transducer (IV) A device that receives an input in electrical form or provides an output in electrical form Choose the correct answer from the options given below:
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