Question

A current carrying loop in a magnetic field is not rotating, under what circumstances it is possible

Answer 1

Torque, T = nIABcosx
 where n= no. of turns in the loop
            I= current in the loop
            A= area of the loop
            B= magnetic field density
            x= angle made by the plane of the loop with the magnetic field

for no rotation , T=0
 this can be possible when x=90 degrees
 so that cosx=cos90=0