MCQ
The audio signal:
- ACan be sent directly over the air for large distance
- BCannot be sent directly over the air for large distance
- CPosses very high frequency
- DNone of above
✓
Answer
- Cannot be sent directly over the air for large distance
Explanation:
An Audio signal may vary from 20Hz to 20KHz, But in general, it is around 200Hz only,.
This Frequency when transmitted directly to air for long-distance is attenuated and a signal is lost in the air, That's why such frequency is first modulated to higher frequencies of order(MHz) and then transmitted to air.
Hence audio signals can't be transmitted directly to air for long distances.
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