Question

GPS needs at least __ signals from satellites for providing geographic location

• A. 1
• B. 3
• C. 2
• D. 4

Hint:

GPS positioning:
- 3 satellites: Determine latitude, longitude, altitude.
- 4 satellites: Correct clock errors (accurate positioning).
- More satellites = better accuracy.

Answer 1

The Correct Option is D

Step 1: Understanding the Question:
This question tests knowledge of the Global Positioning System (GPS).

Step 2: Detailed Explanation:
GPS needs at least 4 (D) satellite signals to provide accurate geographic location.
- 3 satellites: Used to determine latitude, longitude, and altitude (triangulation).
- 4th satellite: Required to correct for clock errors and improve accuracy.
Thus, a minimum of 4 satellites are required for precise positioning.
Other options:
- 1 (A): Not sufficient.
- 3 (B): For basic positioning without altitude correction.
- 2 (C): Not sufficient.
Thus, GPS needs 4 satellites.

Step 3: Final Answer:
Thus, GPS needs at least 4 signals from satellites, which corresponds to option (D).
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