Question

The survey in which the curvature of the earth is taken into account is called:

• A. Topographical survey
• B. Geodetic survey
• C. Plane survey
• D. Hydrographical survey

Answer 1

The correct option is B Geodetic survey

Plane Surveying	Geodetic Surveying
Mean surface of earth is regarded as plane surface.	Actual surface of the earth is taken into consideration.
For small area(< 195.5 km${}^2$)	For larger area (> 195.5km${}^2$)
Line joining two points is a line.	Line joining to point is an arc.
Used in large-scale engineering projects such as bridges dams, highway, etc.	Used in establishing control points for plane survey. This is carried out by dept. of national survey of India.

Note: Hydrographical survey

• This type of survey deals with water bodies like streams, lakes etc.
• It is also called bathymetric surveying which is done to identify physical features present underwater.
• It is the science of measuring all factors beneath water that affect all the marine activities like dredging, marine constructions, offshore drilling etc.
• If is mainly carried out by sensors, sounding or electronic sensor system for shallow water.
• This survey takes part in necessary data collection relating to construction and developments of port facilities, such as pier construction, breakwater construction etc.

Topographical survey

• This type of survey is conducted to locate natural and artificial features present on the earth surface.
• Artificial features are buliding, monuments etc while natural features means hills, rivers etc