question_answer

Two magnets each of magnetic moment M are placed so as to form a cross at right angles to each other. The magnetic moment of the system will be:

A)  M                                          

B)  0.5 M

C)  \[\sqrt{2}\]M                   

D)         2M

Correct Answer: C

Solution :

A bar magnet having north and south poles at its ends is a magnetic dipole.                 Net magnetic moment is s \[M=\sqrt{{{M}^{2}}+{{M}^{2}}}\] \[=\sqrt{2{{M}^{2}}}\] \[=\sqrt{2}\,M\]