objective of Survey



  • The object of surveying:- It is the preparation of a plan and map

  • Plan:- Large scale representation of small areas is called a plan.

  • Map:- Small scale representation of small areas is called a map.
  • Principal of surveying:-

            1. To work from whole to the part

            2. To locate a new station at least two measurement

  • If the curvature of the earth is considered then it is called Geodetic surveying (Area > 250 km2)
  • If the curvature of the earth is not considered then it is called Plane surveying (Area < 250 km2)
  • The difference between the length arch of the circle and subtended chord on the surface of the earth is 0.1m for 18.2km, 0.3m for 54.3km, 0.5m for 91 km
  • Sum of the angles on the spherical triangle on the earth surface & corresponding plane triangle is 1 sec per 195.5 Sq. km area.
  •  The plane angle measured in terms of radians
  • Spherical triangle is measured in terms of steradians

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