MCQ
The audio signal:
- ACan be sent directly over the air for large distance
- ✓Cannot be sent directly over the air for large distance
- CPosses very high frequency
- DNone of above
✓
Answer
Correct option: B.
Cannot be sent directly over the air for large distance
An Audio signal may vary from $20\ Hz$ to $20\ KHz$, But in general, it is around $200\ Hz$ 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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