Question

If at the place, the magnetic bearing of the sun of noon is 182°30', the magnetic declination at that point will be: _____.
1. 2°15'
2. -2°30'
3. 2°30'
4. 3°30'

Answer 1

Correct Answer - Option 2 : -2°30'

Given:

Magnetic bearing of sun at noon = 182° 30'

At Noon, the sun is exactly over the time median of the place. Thus true bearing of the line joining the sun and the place is either 0° and 360° if it is to the north.

and 180° if it is to the south of the place.

Magnetic bearing of sun at noon = 182°30'

True bearing = 180° 

True bearing = M.B + declination

180° - 182°30' = declination

So,

declination = -2° 30'

or declination = 2° 30' W

If value of M.B < 180° 

then,

declination is +ve and Eastern side.