Join 60,000+ competitive exam aspirants
or with email
Your Cart
Subtotal₹0
Total₹0
Examoogle • User • info@examoogle.com • EE-2024-8821
Chapter 1 of 12 • Page 1 of 248🔒 Protected PDF • Watermarked
Join 60,000+ competitive exam aspirants
What is the following procedure should be required for temporary adjustment of theodolite ?
Centering, leveling, Elimination of parallax
leveling, Centering, Elimination of parallax
Centering, Elimination of parallax, leveling
Elimination of parallax, leveling, Centering
Centering, leveling, Elimination of parallax
The temporary adjustments of a theodolite are essential procedures performed at every station to make the instrument ready for observation. The standard sequence is centering, leveling, and elimination of parallax, ensuring the vertical axis is truly vertical and the image is sharply focused on the crosshairs.
The temporary adjustments of a theodolite are essential procedures performed at every station to make the instrument ready for observation. The standard sequence is centering, leveling, and elimination of parallax, ensuring the vertical axis is truly vertical and the image is sharply focused on the crosshairs.
CL=LC1 — Placeholder for optical focusing principle relationship
Centering ensures the vertical axis of the theodolite passes exactly through the ground station mark using a plumb bob or optical plummet. Leveling uses foot screws and plate levels to make the horizontal plate truly horizontal, which is vital for accurate horizontal and vertical angle measurements. Elimination of parallax removes the relative movement between the image of the object and the crosshairs by focusing the eyepiece and the objective lens until the image appears stationary.
Centering ensures the instrument is exactly over the survey station.
Leveling is performed using plate levels and foot screws.
Parallax is eliminated by adjusting the eyepiece (for crosshairs) and objective (for target image).
These adjustments must be repeated if the instrument is disturbed.
Ensures high precision in angular measurements.
Minimizes systematic errors during observation.
Time-consuming for beginners.
Requires manual dexterity for precise leveling.
Traversing
Triangulation
Contouring
Parallax occurs if the image formed by the objective lens does not lie exactly in the plane of the crosshairs.
Option B and D are incorrect because the chronological sequence of setup is specific for ensuring instrument stability and geometric alignment.
A is correct — Centering, leveling, and elimination of parallax is the standard, fixed sequence for temporary adjustment of a theodolite.
Remember the mnemonic 'CLP' (Centering, Leveling, Parallax) to recall the correct order for instrument setup in surveying exams.