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The coercivity of a small magnet where t...

The coercivity of a small magnet where the ferromagnet gets demagnetised is `3xx10^(3)A.m^(-1)` The current required to be passed in a solenoid of length 10cm and number of turns 100 so that the magnet gets demagnetised when inside the solenoid is

A

30mA

B

60mA

C

3A

D

6A

Text Solution

Verified by Experts

The correct Answer is:
C
For solenoid, `B=mu_(0)nI`
`mu_(0)H=mu_(0)nI`
`mu=nI`
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