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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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- The H field in the solenoid is (nearly) unchanged but the B field decreases drastically.
- 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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State the dimensions of magnetization.
Magnetic susceptibility of a diamagnetic substance ______.
Match List-I with List-II.
| List-I (Material) | List-II (Susceptibility) | ||
| A. | Diamagnetic | I. | χ = 0 |
| B. | Ferromagnetic | II. | 0 > χ ≥ −1 |
| C. | Paramagnetic | III. | χ >> 1 |
| D. | Non-magnetic | IV. | 0 < χ < ε |
Choose the correct answer from the options given below:
