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प्रश्न
How do you account for the following fact?
Soft iron keepers help to prevent the magnets from losing their magnetic properties.
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उत्तर
In magnets, external fields like earth’s magnetic field can randomize the domains. Perhaps stray fields caused by flowing currents in nearby electric circuits can also disturb i the alignment of domains lying inside a magnet. Given enough time, such magnets may find their domains randomly oriented and hence their net magnetisation may get lost. A keeper for magnets is just a strong permanent magnet that keeps all the domains pointing the same way and realign those that may have gone astray and hence magnet, can retain its magnetism for a long time.
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