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General
Easy
Question
A uniform, constant magnetic field 
is directed at an angle of 
to the x-axis in the xy-plane, PQRS is a rigid square wire frame carrying a steady current 
, with its centre at the origin O. At time t = 0, the frame is at rest in the position shown in the figure, with its sides parallel to the x and y axes. Each side of the frame is of mass M and length L.. The torque 
about O acting on the frame due to the magnetic field will be
The correct answer is:
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