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Question
The earth’s field departs from its dipole shape substantially at large distances (greater than about 30,000 km). What agencies may be responsible for this distortion?
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Solution
Earth’s field departs from its dipole shape substantially at large distances (greater than about 30,000 km) because of the presence of the ionosphere. In this region, the earth’s field gets modified because of the field of single ions. While in motion, these ions produce the magnetic field associated with them.
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