Solving a problem in physics section 61 point 54 electr

54. A square with side contour l = 30 cm and a current of I = A 5 is oriented in a uniform magnetic field with the magnetic induction B = 0.25 tesla so that its magnetic moment coincides with the field direction. What kind of work is necessary to make A to rotate the loop at an angle α = 180 ° around an axis perpendicular to the direction of the magnetic field? The current is kept constant in a frame.