A bar magnet has coercivity \[4\times {{10}^{3}}\,A{{m}^{-1}}.\] It is – McqOptions

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1.	A bar magnet has coercivity \[4\times {{10}^{3}}\,A{{m}^{-1}}.\] It is desired to demagnetise it by inserting it inside a solenoid 12 cm long and having 60 turns. The current that should be sent through the solenoid is
A.	2 A
B.	4 A
C.	6 A
D.	8 A
Answer» E.

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