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# The coercivity of a small magnet where the ferromagnet gets demagnetized is $\;3 \times 10^{3}\;Am^{-1}\;$ . The current required to be passed in a solenoid of length 10 cm and number of turns 100 , so that the magnet gets demagnetized when inside the solenoid , is :

$(a)\;30\;mA\qquad(b)\;60\;mA\qquad(c)\;3A\qquad(d)\;6A$