Assertion: Substances which at room temperature retain their ferromagnetic property for a long period of time are called permanent magnets. Reason: permanent magnet can be made by placing a ferramagnetic rod in a solenoid and passing current through it.A. If both assertion and reason are true and reason is the correct explanation of assertion.B. If both assertion and reason are true and reason is not the correct explanation of assertion.C. If assertion is ture but reason is false.D. If both assertion and reason are false.

Assertion: Substances which at room temperature retain their ferromagn

1.	Assertion: Substances which at room temperature retain their ferromagnetic property for a long period of time are called permanent magnets. Reason: permanent magnet can be made by placing a ferramagnetic rod in a solenoid and passing current through it.A. If both assertion and reason are true and reason is the correct explanation of assertion.B. If both assertion and reason are true and reason is not the correct explanation of assertion.C. If assertion is ture but reason is false.D. If both assertion and reason are false.
Answer» Correct Answer - B To make a permanent magnet, place a ferromagnetic rod in a solenoid and pass a current through it. The magnetic field of the solenoid magnetises the rod.

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