The magnitude of the magnetic dipole moment of Earth is 8.0×1022JT. a) If the origin...
The magnitude of the magnetic dipole moment of Earth is .
a) If the origin of this magnetism were a magnetized iron sphere at the center of Earth, what would be its radius?
b) What fraction of the volume of Earth would such a sphere occupy? Assume complete alignment of the dipoles. The density of Earth’s inner core is . The magnetic dipole moment of an iron atom is . (Note: Earth’s inner core is in fact thought to be in both liquid and solid forms and partly iron, but a permanent magnet as the source of Earth’s magnetism has been ruled out by several considerations. For one, the temperature is certainly above the Curie point.)