Explain angle of dip.

Explanation

If a magnetic needle is perfectly balanced about a horizontal axis so that it can swing in a plane of the magnetic meridian. The needle would make an angle with the horizontal. This is known as the angle of dip (also known as inclination).

Thus, dip is the angle that the total magnetic field `overset(to) (B_E)` of the Earth makes with the surface of the Earth.

Figure shows the magnetic meridian plane at a point P on the surface of the Earth. The plane is a section through the Earth.
The magnetic field of Earth at point P is `overset(to) (B_E)` .
There are two components of `overset(to) (B_E)`
(1) Horizontal component `overset(to) (H_E)`
(2) Vertical component `overset(to) ((Z_E))`
The angle that `overset(to) (B_E)` makes with `overset(to) (H_E)` is the angle of dip I.
In most of the northern hemisphere, the north pole of the dip needle tilts downwards.
Likewise in most of southern hemisphere, the south pole of the dip needle tilts downwards.