question_answer

A current carrying loop is free to turn in a uniform magnetic field. The loop will then come into equilibrium when its plane is inclined at                    [CBSE PMT 1992; Haryana CEE 1996]

A)            \[0{}^\circ \] to the direction of the field

B)            \[45{}^\circ \] to the direction of the field

C)            \[90{}^\circ \] to the direction of the field

D)            \[135{}^\circ \] to the direction of the field

Correct Answer: C

Solution :

                   In equilibrium angle between \[\overrightarrow{M}\]and \[\overrightarrow{B}\] is zero. It is happened, when plane of the coil is perpendicular to \[\overrightarrow{B}\]