The magnetic field due to the Earth is closely equivalent to that due to:

Explain geographic meridian and magnetic meridian.

$A$ dip needle lies initially in the magnetic meridian when it shows an angle of dip $\theta$ at a place. The dip circle is rotated through an angle $x$ in the horizontal plane and then it shows an angle of dip $\theta'$. Then $\frac{\tan \theta'}{\tan \theta}$ is

The angle of dip at a place is $40.6^\circ$ and the intensity of the vertical component of the earth's magnetic field $V = 6 \times 10^{-5} \text{ Tesla}$. The total intensity of the earth's magnetic field $(I)$ at this place is:

Consider the plane $S$ formed by the dipole axis and the axis of the Earth. Let $P$ be a point on the magnetic equator and in plane $S$. Let $Q$ be a point of intersection of the geographical and magnetic equators. Obtain the declination and dip angles at $P$ and $Q$.

Which of the following relations is correct in the context of Earth's magnetism?