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प्रश्न
Answer the following question.
Why a signal transmitted from a TV tower cannot be received beyond a certain distance? Write the expression for the optimum separation between the receiving and the transmitting antenna.
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उत्तर
The signal transmitted from a TV tower cannot be received beyond a certain distance because of the curvature of the earth. The expression for the optimum separation between the receiving and transmitting antenna:
`d = sqrt(2hR)`
d: Optimum separation.
h: Height of the antenna
R - Radius of the curvature of Earth.
संबंधित प्रश्न
Define modulation and transducer
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I-V characteristics of four devices are shown in Figures.
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| (i) | (ii) | (iii) | (iv) |
Identify devices that can be used for modulation.
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