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प्रश्न
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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उत्तर
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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संबंधित प्रश्न
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(b) magnetic susceptibility and
(c) magnetisation of the rod.
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If a charged particle at rest experience no electromagnetic force
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- electrostatic field lines can end on charges and conductors have free charges.
- lines of B can also end but conductors cannot end them.
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- shells of high permeability materials can be used to divert lines of B from the interior region.
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- Assertion (A): Diamagnetic substances exhibit magnetism.
- Reason (R): Diamagnetic materials do not have a permanent magnetic dipole moment.
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