Find the true bearing of the lines with the following observed magnetic bearings and declinations.
(a) Bearing of line = 189°12. Declination = 2° W
(b) Bearing of line = 72° 44′ Declination = 1° 12 ‘ E
solutions :
(a) True bearing of line= magnetic bearing of line – Declination (West)
= 189° 12′ – 2° 00′
= 187°12′
(b) True bearing of line= magnetic bearing of line + Declination (EAST)
= 72°44′ +1°2′
= 73°56‘
Note:
True bearing = Magnetic bearing + Declination
(b) Declination East
[Use + sign when Declination’ East]
[Use – sign when Declination West]
Magnetic bearing = True bearing + Declination
[Use + sign when Declination West]
[Use – sign when Declination East]