If the height of the tower used for LOS communication is increased by 21%, the percentage change in range is?
- 5%
- 10%
- 15%
- 12%
The Correct Option is B
Approach Solution - 1
\(d=\sqrt{2Rh}, d\propto \sqrt{h}\)
\(d'\propto \sqrt{1.21h} = 1.1h\)
Percentage change in d = 10%
So, the correct option is (B): 10%
Approach Solution -2
For Line-of-Sight (LOS) communication, the range of communication is given by:
\(R = \sqrt{(2 \times h \times d)}\)
where h is the height of the tower and d is the distance to the horizon.
Let's assume that the original height of the tower is h and the original range of communication is R. If the height of the tower is increased by 21%, the new height of the tower is 1.21h. The new range of communication is:
\(R' = \sqrt{(2 \times 1.21h \times d)} = \sqrt{(1.21)} \times \sqrt{(2 \times h \times d)} = 1.1 \times R\)
So the percentage change in range is:
\(\frac{(1.1R - R)}{R}\times100% = 0.1R / R * 100% = 10%\)
Therefore, the percentage change in range when the height of the tower is increased by 21% is 10%.
Hence, the correct option is (B): 10%.
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Concepts Used:
Communication Systems
A system that describes the information exchange between two points is called the communication system. The transmission and reception process of information is called communication. The major elements of communication are such as:
- The Transmitter of information
- Channel or medium of communication
- The Receiver of information
Examples Of Communication Systems:
The following are the examples of communication systems:
- Internet
- Public Switched Telephone network
- Intranet and Extranet
- Television
Types Of Communication Systems:
Turning on Signal specification or technology, the communication system is categorized as follows:
- Analog technology communicates data as electronic signals of differing frequencies or amplitude. For instance Broadcast and telephone transmission.
- In Digital technology, the data are created and processed in two states: High (represented as 1) and Low (represented as 0). Also this technology stores and transmits data in the form of 1's and 0's.
Elements of a Communication System:
