Calculate earths magnetic field?

1. Feb 14, 2007

delta_simon

How do I calculate earths magnetic field at a distance x from earths surface?
Do I have have to think about earth as a dipole and use the rate at the dipole weakens?

2. Feb 14, 2007

Meir Achuz

Yes. Calculate the B field of a dipole at given radius and angle from the N magnetic pole.