Enlist different errors in compass surveying.

Enlist different errors in compass surveying.
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1 Answer

Answer :

Various errors in compass surveying are classified asi) Instrumental errors.

ii) Personal errors or observational errors

iii) Errors caused due to external errors (natural errors)

i) Instrumental errors:

a) Needle is not perfectly magnetized, not pointing to exact meridian.

b) The pivot point is blunt and not sharp

c) Needle is not perfectly straight.

d) Needle and graduated ring is not perfectly horizontal.

e) Object vane is not vertical.

f) Horse hair is not straight.

ii) Personal or observational errors:

a) Inaccurate centering of compass over the station.

b) Inaccurate leveling of compass.

c) Inaccurate bisecting of ranging rod or other objects.

d) Carelessness in taking reading and booking the reading in field book.

iii) Errors due to external influences (magnetic errors):

a) Magnetic disturbances in the atmosphere stormy days.

b) Variations in magnetic declination.

c) Local attraction due to proximity of magnetic substances or magnetic field.
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