Question
Physics Question on Uniform Circular Motion
The coercivity of a small magnet where the ferromagnet gets demagnetised is 3 x 103 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 demagnetised when inside the solenoid, is
A
(A) 3A
B
(B) 6A
C
(C) 30 mA
D
(D) 60 mA
Answer
(A) 3A
Explanation
Solution
Explanation:
μ0H=μ0ni3×103=1000.1×i⇒i=3A