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Compass surveying - Calculation of angle from bearings
Unit 1- Surveying
It is possible when the bearing being measured from common point A
Fig (b) The angle α = (180° + θ1) – θ2
Back bearing of previous line – Fore bearing of next line
From Fig (a) both the bearings have been measured to the same side of common meridian, the included angle α = θ2- θ1,
In Fig (b) both the bearing have been measured to the opposite sides of the common meridian = α = θ1+ θ2,
From Fig (c)both the bearings have been measured to the same side of different meridians and the included angle α = 180°-(θ2 + θ1)
In Fig (d) both the bearings have been measured to the opposite sides of the different meridians and angle α = 180°+ θ2 – θ1.
In Fig (b) both the bearing have been measured to the opposite sides of the common meridian = α = θ1+ θ2,
From Fig (c)both the bearings have been measured to the same side of different meridians and the included angle α = 180°-(θ2 + θ1)
In Fig (d) both the bearings have been measured to the opposite sides of the different meridians and angle α = 180°+ θ2 – θ1.
Last modified: Thursday, 12 May 2011, 4:59 AM