KCET · Physics · Magnetic Properties of Matter
Coersivity of a magnet where the ferromagnet gets completely demagnetized is \( 3 \times 10^{3} \mathrm{Am}^{-1} \)
The minimum current required to be passed in a solenoid having \( 1000 \) turns per metre, so
that the magnet gets completely demagnetized when placed inside the solenoid is
- A \( 3 \mathrm{~A} \)
- B \( 30 \mathrm{~mA} \)
- C \( 6 \mathrm{~A} \)
- D \( 60 \mathrm{~mA} \)
Answer & Solution
Correct Answer
(A) \( 3 \mathrm{~A} \)
Step-by-step Solution
Detailed explanation
(A)
\( H=n l \)
\( \therefore I=\frac{H}{n}=\frac{3 \times 10^{3}}{1000}=3 \mathrm{~A} \)
\( H=n l \)
\( \therefore I=\frac{H}{n}=\frac{3 \times 10^{3}}{1000}=3 \mathrm{~A} \)
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