- Amay increase or decrease in size and change its orientation.
- Bincrease in size but no change in orientation.
- Cdecrease in size and changes orientation.
- Dhave no relation with external magnetic field.
View written solutionFree
Correct answer: A
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Concept of magnetic domains in a ferromagnetic material
A ferromagnetic material consists of many small regions called magnetic domains. Inside each domain, magnetic moments are aligned in the same direction.
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What happens when an external magnetic field is applied?
When a soft ferromagnetic material is placed in an external magnetic field:
- Domains already aligned close to the external field direction grow in size.
- Domains oppositely aligned or less favorably aligned may shrink in size.
- Domain magnetic moments can also rotate/reorient toward the applied field.
Since the material is soft ferromagnetic, domains can change easily under the applied field.
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Check each option
Option A: may increase or decrease in size and change its orientation.
This is correct, because favorable domains grow, unfavorable ones shrink, and domains may reorient.Option B: increase in size but no change in orientation.
Incorrect. Orientation can also change.Option C: decrease in size and changes orientation.
Incorrect. Some domains decrease, but others increase. So this is incomplete/wrong as a general statement.Option D: have no relation with external magnetic field.
Incorrect. Domains respond strongly to the external field. -
Final answer
Therefore, the correct option is:
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Comparison with stored correct answer
Stored correct answer: A
Derived answer: A
Hence, they agree.
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