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Question
Consider the plane S formed by the dipole axis and the axis of earth. Let P be point on the magnetic equator and in S. Let Q be the point of intersection of the geographical and magnetic equators. Obtain the declination and dip angles at P and Q.
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Solution
Let point P is in the plane, S needle is in north, so the declination is zero.
Q is the point of intersection between geographical meridian and magnetic meridian. So angle dip at P and Q will be zero with horizontal as magnetic middle stay horizontally.
As angle between axis of rotation of earth and magnetic axis is 11.3° and their respective equators are at 90° with their respective axis.
From figure,
For point P: Since point P lies in plane S formed by the dipole axis and the axis of the Earth, declination is zero.
For point Q: Since point Q lies on the magnetic equator, angle of dip is zero. Thus the angle of declination is 11.3°.
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