Question

Two identical short bar magnets each having magnetic moment M are placed at a distance of 2d with their axes ⊥  to each other in a horizontal plane. The magnetic induction at a point midway between them is –

• A. $\frac { \mu _ { 0 } } { 4 \pi } \sqrt { 2 } \frac { \mathrm { M } } { \mathrm { d } ^ { 3 } }$
• B.
• C. $\left( \frac { 2 \mu _ { 0 } } { 4 \pi } \right) \frac { \mathrm { M } } { \mathrm { d } ^ { 3 } }$
• D.

Answer 1

Answer: (D)

Answer 2

At P B_net = $\sqrt { \mathrm { B } _ { 1 } ^ { 2 } + \mathrm { B } _ { 2 } ^ { 2 } }$

= $\sqrt { \left( \frac { 2 \mathrm { kM } } { \mathrm { d } ^ { 3 } } \right) ^ { 2 } + \left( \frac { \mathrm { kM } } { \mathrm { d } ^ { 3 } } \right) ^ { 2 } }$ = $\sqrt { 5 }$)