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प्रश्न
What type of substances would make better permanent magnets, ferromagnetic or ferrimagnetic. Justify your answer.
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उत्तर
Ferromagnetic substances would make better permanent magnets.
In solid state, the metal ions of ferromagnetic substances are grouped together into small regions. These regions are called domains and each domain acts as a tiny magnet. In an unmagnetised piece of a ferromagnetic substance, the domains are randomly oriented. As a result, the magnetic moments of the domains get cancelled. However, when the substance is placed in a magnetic field, all the domains get oriented in the direction of the magnetic field and a strong magnetic effect is produced.
The ordering of the domains persists even after the removal of the magnetic field. Thus, the ferromagnetic substance becomes a permanent magnet.
संबंधित प्रश्न
Write the type of magnetism observed when the magnetic moments are aligned in parallel and anti-parallel directions in unequal numbers.
Give reasons:Ferrimagnetic substances show better magnetism than antiferromagnetic substances.
Explain why:
(i) Transition elements form coloured compounds.
(ii) Interhalogen compounds are more reactive than their constituent elements.
(iii) Cu+ is diamagnetic but Cu2+ is paramagnetic. (Z = 29)
Out of [CoF6]3- and [Co(en)3]3+, which one complex is
(i) paramagnetic
(ii) more stable
(iii) inner orbital complex and
(iv) high spin complex
(Atomic no. of Co = 27)
Give reason for the following :
Sulphur in vapour state shows paramagnetic behaviour.
The BH curve for a ferromagnetic material is shown in the figure. The material is placed inside a long solenoid which contains 1000 turns/cm. The current that should be passed in the solenonid to demagnetize the ferromagnet completely is
Compare dia, para and ferromagnetism.
Assertion: On heating ferromagnetic or ferrimagnetic substances, they become paramagnetic.
Reason: The electrons change their spin on heating.
Which of the following arrangements shows schematic alignment of magnetic moments of antiferromagnetic substances?
The value of magnetic moment is zero in the case of antiferromagnetic substances because the domains:
(i) get oriented in the direction of the applied magnetic field.
(ii) get oriented opposite to the direction of the applied magnetic field.
(iii) are oppositely oriented with respect to each other without the application of magnetic field.
(iv) cancel out each other’s magnetic moment.
The heat of combustion of a substance is:
Some of the polar crystals when heated produces small electrical current. This phenomenon is called ______.
Which of the following statements are correct?
- Electric monopoles do not exist whereas magnetic monopoles exist.
- Magnetic field lines due to a solenoid at its ends and outside cannot be completely straight and confined.
- Magnetic field lines are completely confined within a toroid.
- Magnetic field lines inside a bar magnet are not parallel.
- χ = -1 is the condition for a perfect diamagnetic material, where x is its magnetic susceptibility.
The value of aluminium susceptibility is 2.2 × 10-5. The percentage increase in the magnetic field if space within a current carrying toroid is filled with aluminium is `"x"/10^4`. Then the value of x is ______.
Give a reason for the following:
Cu+2 salts are paramagnetic, while Cu+ salts are diamagnetic.
The metal complex ion that is paramagnetic is ______.
(Atomic number of Fe = 26, Cu = 29, Co = 27 and Ni = 28)
