What is the angle between the axis of rotation and the magnetic axis of the Earth (in $°$)?

Give information about the Earth's magnetic field lines and the location of the magnetic poles.

At a given place on the Earth,the angle between the Magnetic Meridian and the Geographic Meridian is called . . . . . . .

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 $..............$ $\times 10^{-6} \,N/m$.

The relations among the three elements of Earth's magnetic field,namely horizontal component $H$,vertical component $V$,and angle of dip $\delta$ are,($B_{E} =$ total magnetic field):

What was the early recognition of Earth's magnetic field? State the dynamo effect.