Question

The magnetic moment of a bar magnet 'A' and its length is twice that of another bar magnet 'B'. Arrange the following steps in sequential order to find the ratio of their pole strengths.

(A) Write the given values of magnet moment $\left(M\right)$ and magnetic length $\left(2l\right)$ of the bar magnets A and B as $M_B=2M_A$and $2l_B=2\left(2l_A\right)$.

(B) Write the expression for pole strength (m) for each magnet using $m=\frac{M}{2l}$

(C) Divide the two expressions to get the ratio of $m_A$ to $m_B$.

• A. BAC
• B. ACB
• C. BCA
• D. ABC

Answer 1

The correct option is D

ABC

Steps to find the ratio of their pole strengths for the magnetic moment of a bar magnet 'A' and its length is twice that of another bar magnet ‘B’ are:

Step 1: (A) Write the given values of magnet moment $\left(M\right)$ and magnetic length $\left(2l\right)$ of the bar magnets A and B as $M_B=2M_A$and $2l_B=2\left(2l_A\right)$.

Step 2: (B) Write the expression for pole strength (m) for each magnet using $m=\frac{M}{2l}$

Step 3: (C) Divide the two expressions to get the ratio of $m_A$ to $m_B$.

Hence, the sequential order to find the ratio of their pole strengths is ABC

Therefore, the correct option is option D.