Quote: Originally Posted by jsp “Second, the current in a closed path will not be in the same direction inside the magnetic field so the net torque will be non zero. Think of a square loop; two sides of the loop will have zero torque on them and the other two sides will have opposite torques so they will add.” Thank you very much, my dear friend, I think that portion of your sentences is correct completely. Indeed, the conclusion of F = ? IB x dL = 0 is not T = IS x B = 0 always.( T = Vector of angle torque and S = Vector of surface of closed induced current circuit) When you rotate the steering wheel of your car, the integration of forces that applied by your right and left hands to it is zero but the applied torque to it isn’t zero. THANKS