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Error due to inaccurate centering comes under ________ error.
Personal
Natural
Instrumental
Personal and natural
Personal
Inaccurate centering of a theodolite occurs due to human oversight or carelessness while setting up the instrument precisely over the station mark using a plumb bob or optical plummet. Since this error depends entirely on the skill, care, and physical limitations of the surveyor, it is classified as a personal error.
Inaccurate centering of a theodolite occurs due to human oversight or carelessness while setting up the instrument precisely over the station mark using a plumb bob or optical plummet. Since this error depends entirely on the skill, care, and physical limitations of the surveyor, it is classified as a personal error.
╬┤╬╕тЙИDeтАЛsin╬▒ тАФ angular error in direction due to centering displacement e at distance D
When the vertical axis of the theodolite is not positioned precisely over the ground station mark, a centering displacement e occurs. This displacement introduces an angular error ╬┤╬╕ in the measured horizontal direction, which varies inversely with the line of sight distance D.
Centering error causes greater angular errors for shorter sight lengths (D).
It belongs to the category of personal (human) errors in surveying.
Using an optical plummet or a precise shifting center helps minimize centering errors.
Option B (Natural) is incorrect because natural errors arise from environmental conditions like wind, temperature, or atmospheric refraction.
Option C (Instrumental) is incorrect because instrumental errors result from imperfections, worn components, or improper adjustments of the instrument itself.
A is correct тАФ Centering error is caused by human limitation and carelessness during instrument setup, making it a personal error.
Always remember: Errors arising from instrument defects are Instrumental, environmental effects are Natural, and human operational limitations/carelessness are Personal.