ExamBro
ExamBro
MHT CET · Physics · Magnetic Properties of Matter

A bar magnet has length 4 cm , cross-sectional area \(2 \mathrm{~cm}^2\) and magnetic moment \(6 \mathrm{Am}^2\). The intensity of magnetisation of bar magnet is

  1. A \(9 \times 10^5 \mathrm{~A} / \mathrm{m}\)
  2. B \(7.5 \times 10^5 \mathrm{~A} / \mathrm{m}\)
  3. C \(4.5 \times 10^5 \mathrm{~A} / \mathrm{m}\)
  4. D \(3.0 \times 10^5 \mathrm{~A} / \mathrm{m}\)
Verified Solution

Answer & Solution

Correct Answer

(B) \(7.5 \times 10^5 \mathrm{~A} / \mathrm{m}\)

Step-by-step Solution

Detailed explanation

Intensity of magnetization
\(\begin{aligned}
& =\frac{M_{\text {net }}}{\text { Volume }} \\
& =\frac{M_{\text {net }}}{\text { length } \times \text { area of cross-section }} \\
& =\frac{6}{\left(4 \times 10^{-2}\right) \times\left(2 \times 10^{-4}\right)}=7.5 \times 10^5 \mathrm{~A} / \mathrm{m}
\end{aligned}\)