Advertisements
Advertisements
प्रश्न
What type of substances would make better permanent magnets, ferromagnetic or ferrimagnetic. Justify your answer.
Advertisements
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
What type of magnetism is shown by a substance if magnetic moments of domains are arranged in same direction?
Define the following term:
Ferromagnetism
Write the type of magnetism observed when the magnetic moments are aligned in parallel and anti-parallel directions in unequal numbers.
Analysis shows that nickel oxide has the formula Ni0.98O1.00. What fractions of nickel exist as Ni2+ and Ni3+ ions?
Explain the following with suitable examples:
Paramagnetism
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)
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

What happens to the domains in a ferromagnetic material in the presence of external magnetic field?
Substances which are weakly repelled in magnetic field are known as ____________.
All those atoms or molecules which have an odd number of electrons are
Fe3O4 is ____________.
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?
Which of the following statements is not true?
Which one of the following pairs has only paramagnetic species?
Some of the polar crystals when heated produces small electrical current. This phenomenon is called ______.
Match items of List - I with those of List - II:
| List - I | List - II | ||
| (Property) | (Example) | ||
| (A) | Diamagnetism | (i) | MnO |
| (B) | Ferrimagnetism | (ii) | O2 |
| (C) | Paramagnetism | (iii) | NaCl |
| (D) | Antiferromagnetism | (iv) | Fe3O4 |
Choose the most appropriate answer from the options given below:
