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प्रश्न
Distinguish between ‘paramagnetic’ and ‘ferromagnetic’ substances.
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उत्तर
| Sr. No. | Paramagnetic | Ferromagnetic |
| 1. | Substances which are weakly attracted by a magnet are called paramagnetic substances. | Substances which are strongly attracted by a magnet are called ferromagnetic substances. |
| 2. | Paramagnetic materials lose their magnetism on removal of the external field and hence cannot be used to make permanent magnets. | Ferromagnetic materials retain some magnetism on removal of the external field and hence can be used to make permanent magnets. |
| 3. | The susceptibility is positive but small. | The susceptibility is positive but very high. |
| 4. | In the absence of an electric field, the net dipole moment is zero. | In the absence of an electric field, the net dipole moment is non-zero. |
| 5. | Aluminium, manganese, chromium and platinum are some examples of paramagnetic substances. | Iron, nickel, cobalt, gadolinium, dysprosium and their alloys are some examples of ferromagnetic substances. |
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| (a) | (b) |
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