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प्रश्न
Distinguish between diamagnetic and paramagnetic substances.
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उत्तर
| Sr. No. | Diamagnetic substance | Paramagnetic substance |
| 1. | In an external magnetic field, a substance gets weakly magnetised in the direction opposite to that of the field. | In an external magnetic field, a paramagnetic substance gets weakly magnetised in the same direction as that of the field. |
| 2. | When placed in a non-uniform magnetic field, it tends to move from the stronger to the weaker part of the field. | When placed in a non-uniform magnetic field, it tends to move from the weaker to the stronger part of the field. |
| 3. | It is weakly repelled by a magnet. | It is weakly attracted by a magnet. |
| 4. | Magnetic moment of every atom of a diamagnetic substance is zero. | Every atom of a paramagnetic substance is a magnetic dipole having a certain resultant magnetic moment. |
| 5. | When a rod of diamagnetic substance is suspended in a uniform magnetic field, it comes to rest with its length perpendicular to the direction of the field. | When a rod of paramagnetic substance is suspended in a uniform magnetic field, it comes to rest with its length parallel to the direction of the field. |
| 6. | There is no effect of temperature on diamagnetic substance. | There is effect of temperature on paramagnetic substance. |
संबंधित प्रश्न
Distinguish between ‘paramagnetic’ and ‘ferromagnetic’ substances.
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Identify the following magnetic materials :
Choose the correct option:
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- The H and B fields in the solenoid are nearly unchanged.
- The magnetisation in the core reverses direction.
- The magnetisation in the core diminishes by a factor of about 108.
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Explain ferromagnetism on the basis of the domain theory.
Explain the meaning of the following statement:
Curie temperature for soft iron is 770°C.
