Define orientation. State two methods of orientation. Which method is most accurate and why?

Define orientation. State two methods of orientation. Which method is most accurate and why? 
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1 Answer

Answer :

Orientation is the process of keeping plane table in same position as that is occupied in previous station.

Methods of orientation:

i) Magnetic meridian method using trough compass

ii) Back sighting method using alidade

Out of two, the most accurate method is orientation by back sighting.

Because in this method orientation is done by using alidade and not by using trough compass. Therefore there is no error occurring due to local attraction.
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