Question

Two similar bar magnets P and Q, each of magnetic moment M, are taken, If P is cut along its axial line and Q is cut along its equatorial line, all the four pieces obtained have

• A. Equal pole strength
• B. Magnetic moment $\frac { M } { 4 }$
• C. Magnetic moment $\frac { M } { 2 }$
• D. Magnetic moment M

Answer 1

Answer: (C)

Magnetic moment $\frac { M } { 2 }$

Answer 2

If pole strength, magnetic moment and length of each part are $m ^ { \prime } , M ^ { \prime }$and $L ^ { \prime }$respectively then

$m ^ { \prime } = \frac { m } { 2 }$ $m ^ { \prime } = m$

$L ^ { \prime } = L$ $L ^ { \prime } = \frac { L } { 2 }$

$\Rightarrow M ^ { \prime } = \frac { M } { 2 }$ $\Rightarrow M ^ { \prime } = \frac { M } { 2 }$