Taking observations on both Face Left and Face Right with a theodolite eliminates:
Choose the correct answer
Parallax error in target sighting
Line of collimation error and horizontal axis error (by averaging FL and FR)
Levelling error in the bubble
Effect of magnetic declination
Correct Answer
B. Line of collimation error and horizontal axis error (by averaging FL and FR)
Why is this the answer?
Face Left (FL) + Face Right (FR) eliminates: (1) Line of collimation error (non-perpendicularity of line of sight to horizontal axis); (2) Horizontal axis error (trunnion axis not horizontal). Mean of FL and FR readings eliminates these. Circle graduation error eliminated by multiple sets with different initial settings.
Related Surveying MCQs
More solved Surveying questions for AE/JE Civil Engineering exams.
- A 'Digital Elevation Model' (DEM) is used in GIS for:
- 'Contour interval' selection for a topographic survey depends on:
- The 'photogrammetric control' (ground control points) in aerial survey are required for:
- The 'EDM' (Electronic Distance Measurement) instrument measures distances using:
- The 'photogrammetric stereomodel' from two overlapping aerial photos allows...
- The 'corrections' applied to measured chain/tape lengths include all EXCEPT:
Practice more Civil Engineering questions
This MCQ belongs to JE Level Premium Test Series. Full tests include timed attempts, rank comparison and subject-wise analysis.