Question

Coercivity of a magnet where the ferromagnet gets completely demagnetized is 6 x 10³ Am^-1. The minimum current required to be passed in a solenoid having 2000 turns per metre, so that the magnet gets completely demagnetized when placed inside the solenoid is ____________.

Options

• 3 A

• 30 mA

• 6 A

• 60 mA

Answer 1

Coercivity of a magnet where the ferromagnet gets completely demagnetized is 6 x 10³ Am^-1. The minimum current required to be passed in a solenoid having 2000 turns per metre, so that the magnet gets completely demagnetized when placed inside the solenoid is 3 A.

Explanation:

H = nl

`"I" = "H"/"n"`

` = (6 xx 10^3)/2000`

`= 3  "A"`