The coercitivity of a small magnet where the ferromagnet gets demagnetized is `3 xx 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. `3A`B. `6A`C. `30mA`D. `60mA`

The coercitivity of a small magnet where the ferromagnet gets demagnet

1.	The coercitivity of a small magnet where the ferromagnet gets demagnetized is `3 xx 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. `3A`B. `6A`C. `30mA`D. `60mA`
Answer» Correct Answer - A Here, coercivity of given magnet `=B/mu_0=3xx10^3Am^-1` As `B=(mu_0NI)/(L)` or `I=(BL)/(mu_0N)=((3xx10^3)xx0*1)/(100)=3A`

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The coercitivity of a small magnet where the ferromagnet gets demagnetized is `3 xx 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. `3A`B. `6A`C. `30mA`D. `60mA`

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