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प्रश्न
Define modulation and transducer
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उत्तर
Modulation:-
The process of superimposing a low frequency signal on a high frequency wave, which acts as a carrier wave for long distance transmission is known as modulation.
Transducer:-
A transducer is a device, which converts one form of energy into another.
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संबंधित प्रश्न
Define modulation index.
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Given modulation index physical significance .For an amplitude modulated wave, the maximum amplitude is found to be 10 V while the minimum amplitude is 2 V. Determine the modulation index μ ?
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An audio signal of 15kHz frequency cannot be transmitted over long distances without modulation because ______.
- the size of the required antenna would be at least 5 km which is not convenient.
- the audio signal can not be transmitted through sky waves.
- the size of the required antenna would be at least 20 km, which is not convenient.
- effective power transmitted would be very low, if the size of the antenna is less than 5 km.
A 25 m long antenna is mounted on an antenna tower. The height of the antenna tower is 75 m. The wavelength (in meter) of the signal transmitted by this antenna would be ______.
A carrier wave Vc(t) = 160 sin(2π × 106t) volts is made to vary between Vmax = 200 V and Vmin = 120 V by a message signal Vm(t) = Am sin(2π × 103t) volts. The peak voltage Am of the modulating signal is ______.
A transmitting antenna has a height of 320 m and that of receiving antenna is 2000 m. The maximum distance between them for satisfactory communication in line of sight mode is 'd'. The value of 'd' is ______ km.
