The type of surveying in which the curvature of the earth is taken into account is called ........
🌍 Defining Geodetic Surveying
Geodetic surveying is the specific branch of surveying that accounts for the true shape and curvature of the Earth. It is essential for large-scale projects where high precision is required.
Key Characteristics of Geodetic Surveying:
- The Earth's surface is treated as a spheroid (curved).
- Lines connecting points on the surface are considered arcs.
- It uses highly precise instruments and methods.
- Calculations involve complex spherical trigonometry.
- It is necessary for survey areas typically larger than 250-260 km².
🤔 Why Other Options Are Incorrect
Understanding the other terms helps clarify why Geodetic surveying is the only correct answer:
Plane Surveying: This is the direct opposite of geodetic surveying. It ignores the Earth's curvature and treats the survey area as a flat plane. It is only suitable for small areas.
Topographical Surveying: This type of survey focuses on identifying and mapping the natural and man-made features of an area (e.g., hills, rivers, buildings, roads). It can be either plane or geodetic, depending on the size of the area, but its primary purpose is feature mapping, not accounting for Earth's shape.
Preliminary Surveying: This is a phase of a project, not a type of surveying based on curvature. It involves reconnaissance and initial data collection to determine the feasibility of a project and select the best routes or locations.
📊 Quick Comparison
| Type of Surveying | Considers Earth's Curvature? | Primary Purpose |
|---|---|---|
| Geodetic Surveying | Yes (Essential) | High-precision mapping of large areas (e.g., countries, control networks). |
| Plane Surveying | No (Ignored) | Mapping small areas for engineering and property projects. |
| Topographical Surveying | Depends on Area Size | To map physical features and elevations on the ground. |