Question

The angle between the true north – south line and the magnetic north south line is known as _ _ _ _
A. Magnetic bearing
B. Magnetic variation
C. Magnetic Declination
D. True bearing

Answer 1

Hint: Two key northern variants exist the true north and the magnetic north. A third version, grid north, is also available, but this is not connected to magnetic declination. True north is a geographical direction represented by lines of longitude on maps and globes. Each longitude line starts and ends at the poles of the Earth and reflects direct travel north and south.

Complete Answer:
Magnetic declination is known as the angle between the true north-south line and the magnetic north-south line. The angle on the horizontal plane between magnetic north (the direction of the north end of the magnetized compass needle points, equivalent to the direction of the magnetic field lines of the Earth) and true north is magnetic declination, or magnetic variation (the direction along a meridian towards the geographic North Pole). This angle varies depending on the location of the surface of the Earth.

By convention, when the magnetic north is east of the actual north, declination is positive, and when it is west, negative. Isogonic lines are lines on the surface of the Earth along which the declination has the same constant value and agonic lines are called lines along which the declination is zero. As the symbol for magnetic declination, the lowercase Greek letter δ (delta) is also used.

The right answer is option C (Magnetic Declination).

Note: Magnetic declination, also known as magnetic dip, which is the angle between the magnetic field lines of the Earth and the downward side of the horizontal plane, should not be confused with magnetic inclination.