question_answer

Two identical thin bar magnets each of length l and pole strength m are placed at right angle to each other with north pole of one touching south pole of the other. Magnetic moment of the system is                            [MNR 1981; MP PET 2002]

A)            ml  

B)            2ml

C)            \[\sqrt{2}ml\]                      

D)            \[\frac{1}{2}ml\]

Correct Answer: C

Solution :

                   \[{{M}_{net}}=\sqrt{2}M=\sqrt{2}ml.\]