The top of a mast signal 2000m away was sighted through a transit with recorded vertical angle of 4 deg. 10 min. the height of the mast is 6m and the HI of the transit above the point where it is set is 1.2m. The elevation of the base of the signal B is 171.17m. Compute the elevation of the point under the transit A with due allowance for curvature and refraction correction.

Q: To test its line of sight adjustment, a level is set up near C (elev. 193.436 m) and then near D.…

A: station C elevation is given as 193.436 mwhen setup is near C: station C reading =1.315 m…

Instruments for Surveying

Surveying is the practice that determines the relative three-dimensional positions of many different points on the earth’s surface. There are various instruments used in Surveying like Theodolites, Total station, Tripod stands, Plane table, etc. for measuring horizontal angle, vertical and sloping angle, which are very useful for giving accurate and precise measurement.