The ratio between the total intensity of the magnetic field at the equator to the poles is:

Define the angle of dip and the angle of declination.

At a certain place,the angle of dip is $30^{\circ}$ and the horizontal component of the Earth's magnetic field is $0.5 \ G$. The Earth's total magnetic field (in $G$) at that place is:

The horizontal component of Earth's magnetic field at a place is $3.5 \times 10^{-5} \,T$. $A$ very long straight conductor carrying a current of $\sqrt{2} \,A$ in the direction from South-East to North-West is placed. The force per unit length experienced by the conductor is $..............$ $\times 10^{-6} \,N/m$.

$A$ compass needle which is allowed to move in a horizontal plane is taken to a geomagnetic pole. It

$A$ line passing through places having zero value of magnetic dip is called